Red Sox outfielder Mike Cameron received an initial diagnosis of a kidney stone on Thursday in Minnesota, his agent, Mike Nicotera, confirmed in a text message. (The news was first reported by ESPN’s Gordon Edes.) Nicotera said that Cameron, who is back in Boston, will receive a “full workup today” and that more about his prognosis (including his expected duration on the sidelines) will be known once that is complete.

The Sox had been hoping to rule out appendicitis for the 37-year-old outfielder, who is currently hitting .217/.357/.261/.618. An appendectomy would have all but guaranteed a trip to the disabled list for the center fielder.

While a kidney stone would represent a less severe issue, however, it does not necessarily mean that Cameron will be returning in the immediate future. In recent seasons, there are instances of players who have spent no more than a few games sidelined by the condition (Marlon Byrd and Bobby Jenks both missed three games due to kidney stones last year) and others (such as Miguel Olivo in 2004) who have landed on the disabled list with the condition. In 2006, Coco Crisp was delayed by more than a week in his return from a broken index finger due to kidney stones.

With Cameron and Jacoby Ellsbury (sore ribs) ailing, the Red Sox may need to dip into the minor leagues for a replacement as they prepare to host the Tampa Bay Rays in a four-game series. Click here to read about one of the candidates, Pawtucket Red Sox outfielder Josh Reddick.

According to multiple reports, Red Sox outfielder Mike Cameron will be checked in a Minneapolis hospital for an examination of the lower abdominal pain that kept him out of the lineup on Thursday. The team wants to rule out appendicitis (a condition that would require surgery and prevent Cameron from flying) before allowing him on a plane.

Meanwhile, outfielder Jacoby Ellsbury told reporters after the Sox’ 8-0 loss to the Twins that he continues to experience “sharp pain” when trying to take a deep breath. He will be further examined in Boston on Friday.

Until either Ellsbury or Cameron can return, the Sox have only three outfielders on their roster: J.D. Drew, Jeremy Hermida and Bill Hall. That being the case, if both remain unavailable for the team’s return to Boston, a minor league addition would be expected.

Josh Reddick is the only Red Sox minor league outfielder on the 40-man roster. He was not in the starting lineup for Triple-A Pawtucket’s game in Buffalo on Thursday, but PawSox skipper Torey Lovullo told reporters that Reddick was out for a “mental break” following a 4-for-29 start to the season.

FORT MYERS, Fla. — For Josh Beckett, the success of his first start of the Grapefruit League season was easy to measure. Beckett allowed a run on two hits in two innings, striking out one, walking none, and throwing 19 of his 27 pitches for strikes. Yet he defined his effectiveness with another gauge.

“I feel like I kept the ball down well. There were five groundballs [and] two hits – one a line drive, the other a groundball,” said Beckett. “Things we’ve been working on the last two weeks, I’m getting there.”

That Beckett would now measure the success of his performance in terms of grounders represents an interesting evolution of his approach. In 2009, he matched his career best groundball-to-flyball ratio (0.91 to 1, compared to a big league average of 0.81-to-1) and set a new career standard by producing 1.28 groundouts per flyout (more than 20 percent better than the MLB average of 1.06-to-1).

The 29-year-old says that he has not been trying to redefine himself as a groundball pitcher, but that the area of emphasis in his game over the last two seasons has lent itself to a development in that direction. He has incorporated a two-seam fastball that has become as much a swing-and-miss pitch as a groundball-inducing one. As much as that two-seamer with both tail and sink, his ability to work down in the strike zone with his four-seam fastball (the primary pitch that he featured on Thursday) has been a huge factor in his increasing talent for keeping the ball on the ground.

“I think just keeping the ball down, you’re going to get more groundballs,” said Beckett. “The top half of the ball is more exposed than the middle part and the bottom, so I think you’re just going to get more groundballs by keeping the ball down.”

–Of the 13 pitches that Jonathan Papelbon threw in his first inning of Grapefruit League action, he estimated that he threw four splitters. That, of course, is a pitch that Papelbon has prioritized this spring in an effort to present opponents with a broader mix of pitches for which they must account.

Though the pitch didn’t result in any swings and misses on Thursday, Papelbon seemed pleased with the action of his splitter, including one that resulted in a foul ball straight into the ground and another that produced a called strike.

Papelbon suggested that he has taken a greater focus into spring this year. He is not shy about saying that his goal is greatness, and that after some struggles in 2009 (and a season that ended on a note of disappointment, when his 0.00 ERA in the postseason finally took a hit in Game 3 of the ALDS), he is driven to make the needed adjustments.

“I think the day I stepped foot in a big league uniform I’ve always strived to be a great athlete,” said Papelbon. “But I’ve also said too [that] to be a great athlete comes with a lot of hard work and a lot of challenges and a lot of adjustments.

“I feel like right now, I’m just in a phase in my career where I’m having to make adjustments and having to realize the challenges ahead of me and evolve my game. I see how it is – it’s very simple when you look at it. It’s just an evolving time for my game and who I am and what I do.”

–The double play tandem of Marco Scutaro and Dustin Pedroia got its first unveiling in a game, and the results were solid. In particular, Beckett praised the pair for turning a double play when Scutaro ranged to his right on a hard-hit ball by Michael Cuddyer to start a 6-4-3 double play.

“That was a great double-play on a 3-and-1 pitch. That’s the pitch I’ve been talking about since day one of spring training. You don’t have to make a perfect pitch. You make a decent pitch, and the guys behind you pick you up,” said Beckett.

“I don’t think [the pitchers] have talked about [the defensive improvement], but I think it’s just known. Obviously the defense is really going to help us with not having to make the perfect pitch. They’re bad situations for us when we’re behind in the count with guys on base, but I feel like you can just make a good pitch, and if the ball is put in play, you’ve got a good chance of getting some outs.”

–Catcher Mark Wagner delivered the game-winning hit for the Red Sox after entering the game in the top of the eighth inning. He lined a single to left with Josh Reddick (who lined a leadoff double to right) on third to break a 1-1 tie in the bottom of the eighth. Reddick’s ball had surprising carry to right field on a chilly night, and Twins right fielder Rene Tosoni misjudged it, thus permitting it to sail over his head.

–The Sox bullpen combined to produce seven shutout innings. Scott Atchison got the win with a scoreless eighth, and Joe Nelson had the save by putting up a zero in the ninth.

FORT MYERS, Fla. — The pace of activity is picking up as new arrivals fill the crowded clubhouse in the Red Sox’ minor league training facility. With all position players scheduled to report for spring training today, the roster is taking fuller shape. David Ortiz arrived early on Monday morning, one day after Bill Hall, intent on reviving his career and restoring the swing mechanics that he lost after an ankle injury in 2007, tried to acclimate to his new spring training facility.

Even as the shape of the 2010 team takes further definition, a significant amount of attention is falling on the Red Sox future. There are plenty of questions this spring about what the future holds for potential free agents Josh Beckett and Victor Martinez following this season.

Beckett addressed his situation (sort of) in a meeting with the media. Martinez, meanwhile, spoke with Lou Merloni about the fact that he is somewhat bemused by questions about whether he is still an everyday catcher. Martinez also reiterated that he would love to stay in Boston, but that while he is open to negotiating an extension, he wants to conclude any conversations about his contract by the end of spring training.

Meanwhile, Red Sox infield instructor Tim Bogar came away dazzled from a glimpse into the slightly more distant future after his first chance to look at shortstop Jose Iglesias in the field. Noteworthy: multiple baseball sources say that Iglesias was offered more to sign with the Cubs than the $8.25 million he received from the Sox.

As for the 2010 season, pitching coach John Farrell broke down what each of the returning pitchers on his staff is working on in spring training. Dustin Pedroia made clear that he is no great fan of the more advanced defensive metrics and the ongoing offseason chatter that the Sox are now a team that will rely heavily on “run prevention” to win. Beckett, meanwhile, said that he wasn’t overly concerned with titles such as that of “the ace,” and that his focus is simply on figuring out a way to compete on any given day, regardless of what kind of stuff he has.

QUOTABLE

“I wish he went to the National League. Good sign for Detroit, though. [Tigers manager Jim] Leyland will love him. He really will. But I’m not sad he’s not in our division. You can talk all you want about maybe his decreasing defensive skills or however you want to say it. When he’s coming up to bat, it’s not a good feeling. He’s shooting balls all over the ballpark, over the third base dugout, bouncing one into your dugout, looks over and waves at you, then he hits the ball into the gap and it’s a double. Not sad to see him move on.” — Manager Terry Francona on Detroit’s signing of Johnny Damon

INJURY REPORT

Daisuke Matsuzaka continues to move well in drills, and is scheduled to play catch from 60 feet on Monday. Though he had been expected to do so on Sunday, that was a byproduct of Francona’s confusion about the day of the week.

NO MINOR DEVELOPMENTS

–Yamaico Navarro has been a batting practice beast, threatening cars on Edison Ave. while mashing balls over the fence in left and left-center. His raw power is significant. Navarro said that his wrist (which required surgery to remove a broken hamate) feels “perfect” this spring, and that he is “stronger than ever.”

–Lars Anderson also put on a show in batting practice, using his smooth swing to flash all fields power. Anderson says that he is in a “very good place” after his struggles in 2009.

–Josh Reddick said that he’s currently at his typical playing weight of about 180 pounds. He said that he actually weighs less now than he did in college, when he weighed 188 pounds at Middle Georgia.

The Red Sox’ Rookie Development Program, which helps to prepare players who could be in line for promotions to the major leagues within a 12- to 18-month timeframe, began today. The two-week program offers top Red Sox minor leaguers the opportunity to work with members of the major-league coaching staff, to work on strength and conditioning as well as fundamentals, and a chance to become familiar with such details as the layout of the clubhouse at Fenway Park.

The release — which also includes details of an autograph session with the prospects — is below. For a closer look at the program participants, click here. Josh Reddick — who also took part in the program last year — was added to the initial roster of 11 program participants. For a closer look at the right-fielder’s path to the majors, click here.

BOSTON, MA– The Red Sox 2010 Rookie Program began today in Boston.  Twelve of Boston’s top prospects are taking part in the two-week program, which is designed to expose the players to the expectations of being Major Leaguers for the Red Sox.

Eleven of the participants in the Rookie Program spent all of 2009 in the Red Sox organization: pitchers Randor Bierd, Felix Doubront, Casey Kelly, Ryne Miller, Junichi Tazawa, Kyle Weiland; catcher Luis Exposito; infielder Yamaico Navarro; and outfielders Ryan Kalish, Che-Hsuan Lin and Josh Reddick. Also taking part will be infielder Jose Iglesias, who was signed as a free agent in September 2009 and played in the Arizona Fall League.

The program includes two workouts daily that emphasize conditioning and strength training as well as concentration on fundamentals. In addition, the players are attending a number of seminars that will focus on the assimilation into Major League life off the field.

A number of individuals will speak to the group, including President/CEO Larry Lucchino, General Manager Theo Epstein, manager Terry Francona, Major League coaches John Farrell and Dave Magadan, sports psychology coach Bob Tewksbury, right-handed pitcher John Lackey, infielder Kevin Youkilis, Hall of Fame baseball writer and NESN reporter/analyst Peter Gammons, and Boston Celtics head coach Doc Rivers.

There will also be a public autograph signing with the Rookie Program participants at the Best Buy in the Landmark Center, located at 401 Park Drive in Boston on Monday, January 18 from 3:30 p.m. until 5:00 p.m. Fans making a $20.00 donation to the Red Sox Foundation will be able to take part in the signing on a first come, first served basis.

Baseball America released its Top 10 Red Sox prospects on Wednesday. Ryan Westmoreland, who is recovering well from a season-ending broken clavicle, was named the organization’s top prospect. Westmoreland is regarded as a five-tool talent, and some talent evaluators have likened his abilities to those of Indians star centerfielder Grady Sizemore. Westmoreland was followed on the list by right-handed pitcher Casey Kelly, who recently made the decision to become a full-time pitcher, and is expected to compete for a spot in Double A Portland in spring training.

Last year’s top-rated Sox prospect, Lars Anderson, slipped to fourth on the list, between outfielders Josh Reddick and Ryan Kalish.

For Baseball America’s complete Top 10, click here.

INDIANAPOLIS — Red Sox GM Theo Epstein met with the media to discuss what has been accomplished at the Winter Meetings in Indianapolis. He will be leaving tomorrow morning, shortly after the Rule 5 draft, and he doesn’t anticipate that any major moves will occur before departing. Presumably, that would include anything to do with either Jason Bay (whose agent, Joe Urbon, has not met with Epstein today) or Matt Holliday (whose agent, Scott Boras, has met with Epstein today, armed with books on the outfielder).

Indeed, Epstein said that one of the foremost accomplishments of the meetings to date has been the club’s ability to rule out and narrow down some of its options, and to eliminate potential free agents or trade targets from its shopping list. He did offer the following specifics, including:

–The club has one potential non-tender candidate for salary arbitration. Epstein declined to identify the individual, but in all likelihood, the candidate is first baseman Casey Kotchman, who made $2.25 million in 2009, and would be due a bump in salary arbitration, despite not having a starting role.

–The Sox have already achieved some improvement in its defense with the acquisition of Marco Scutaro, who is superior to the combined group that the Sox had at the position last year, but that it was certainly open to doing more. That said, he said that the team would likely have to choose between adding offense or defense at this point.

–Prospect Josh Reddick is likely to spend more time in Triple A to start the year, and that he would benefit from further development. Epstein described the 22-year-old as unlikely to ever have high walks totals, but that he makes consistent hard contact and plays good defense.

Highlights of his media session follow:

What have you accomplished today?

I think we’ve narrowed a few things down and had some more productive talks today. I think there was progress on a few small- to medium-sized things.

Safe to say you won’t have a transaction between now and leaving?

I don’t think we’ll make a blockbuster between now and then, but something small could always come up.

What have you narrowed down?

Some free-agent price tags are well beyond our evaluation of a player. So we’ve eliminated that possibility for now. Some trade talks, some players are not available or they’re looking for players that we don’t match up with. We’ve been able to narrow our focus a little bit. Our talks, instead of contemplating the whole universe of possibilities, now we’re down to some things that clearly are realistic.

Anything going on with Bay?

No. Nothing. Those guys [Bay's representatives] are off doing their thing.

Talking to other teams?

I assume.

Do you pay attention when Scioscia says Bay isn’t part of Angels’ plans?

For any free agent, there can be a significant market or less of a market, but I think it’s hard to read it through press comments. If you try to determine exactly what teams might be on a certain player, you can often err and be overconfident, or you can panic and overreact. It’s better just to focus on what makes sense for you. Obviously, there’s a little bit of a supply and demand dynamic that comes into play. But you just try to focus on signing the player at a cost that makes sense for the organization, regardless.

Is it safe to say you didn’t talk to Bay’s representatives today?

Not yet.

Have you met with Boras?

Yeah, we met today. We got the books. … He busted out the books. I said, ‘I wish you hadn’t given those to me. I just told our media that we didn’t read books ever, and that we aren’t a well-read organization.’ They were impressive. They were hard.

What can you say about Ramon A. Ramirez, the reliever who was acquired on waivers?

He’s a versatile guy who’s had a lot of success out of the bullpen. If you look at his performance, he’s done really well in shorter stints. That intrigues us. Then, the ability to start and carry some innings. He’s started quite a bit. He’s a guy who’s a strike thrower with a good changeup who our scouts like, and can come into camp and compete for a variety of roles. If something opens up in our rotation, he’ll compete for a rotation spot. If not, he’ll compete for the bullpen. He’s also got options.

Do you anticipate Rule 5 activity?

We’re highly unlikely to be active.

Have you changed your Rule 5 approach?

The crop is nowhere near as good as it used to be, because they changed the rule.

Teams are able to protect a greater percentage of their quality prospects. You’re really looking at A ball and below, or the stray Double A or Triple A guy coming off a horrible year.

Think you might lose anyone?

I think we might. I think there are a couple guys. … If we lose guys, we have an expectation that we would be able to get them back.

Did you accomplish your desired defensive upgrade with Scutaro?

I think that it certainly improved our defense at the shortstop position over the totality of our performance last year at that position so that’s a big help. That’s an important position. I think we could do more, certainly. Whether we’re able to or not remains to be seen. I think it will be hard to improve both on offense and with our defense but I’m not sure which direction it will go yet.

How do you view the outfield?

When it’s all said and done, I think we’re going to have a really good outfield. I think we kind of quietly had one of the better outfields in all of baseball last year, if you look at what Drew did, what Bay did and the progress that Jacoby made was pretty darn good. We’d like to have that again.

Do you have any non-tender candidates?

Yeah, we have one non-tender candidate.

Is there any trade interest in him?

Possibly.

How do you view the possibility of signing older relievers, who likely want a shorter-term deal?

I think with any older player in free agency, there are plusses and minus’s. you have an established track record, which is good. You have experience. You have a feel for the players’ makeup. Maybe there’s some leadership skills that go along with it. and you usually have the opportunity for a shorter contract, whether it’s one year or two years. Usually the older players aren’t looking for the long term commitments. You limit your risk a little bit even though you’re likely to experience some decline the term of the contract. Whether that represents value or not usually depends on whether the player continues to perform or ages during the term of the contract, even if it’s a one or two year deal. There’s risk/reward with a shorter contract for an older player just like there is on conceivably a longer contract for a younger player but you do limit your risk because the total outlay of dollars is probably less. So if you’re confident it’s a player that takes care of himself and you have reason to believe he’ll age well, or he’s starting from a high peak, you can find value there. You can also get burned there.