Outfielder Mike Cameron helped key the Red Sox' victory over the Giants. (AP)

For the second day in a row, it was a game that had disaster stamped all over it for the Red Sox. After enduring a loss and, more painfully, the loss of Dustin Pedroia to a non-displaced foot fracture on Friday, the Sox watched in what must have bordered on horror as starter Clay Buchholz pulled up lame while running the bases (following his first big-league hit) in the top of the second inning.

Buchholz left the game with what was diagnosed by the Sox as a hyperextended left knee. The Sox were relieved by the initial diagnosis, which suggested that the injury is not considered serious.

Still, with Buchholz (the team leader in wins with 10 and ERA with a 2.45 mark) knocked out after just one inning on the mound, the Sox were left to scramble for innings. In an impressive collective effort by the bullpen, a combined seven relievers did just that, steering the team to a 4-2 victory in San Francisco, giving the Sox their second win in the first five games of this road trip to National League parks.

WHAT WENT RIGHT FOR THE RED SOX

–The bullpen’s tremendous effort was highlighted by a few key contributions:

• Scott Atchison entered for the bottom of the second and logged 2 1/3 innings, allowing just one run. His ability to work through 42 pitches played a huge role in getting the Sox bullpen aligned.
• Dustin Richardson inherited a first-and-third, no-out situation in the bottom of the sixth and the Sox leading, 4-1. In one of the pivotal sequences of the game, the rookie left-hander struck out Pablo Sandoval, got Buster Posey to fly out (for a sac fly) and elicited a fielder’s choice groundout from Aaron Rowand.
• Hideki Okajima struck out a pair in a scoreless seventh, showing one of his better curveballs of recent weeks.
• Jonathan Papelbon, in his first appearance since blowing saves on back-to-back nights in Colorado, was surgically efficient in a perfect ninth inning for his 17th save of the year.

–Mike Cameron finally hit his first homer as a member of the Red Sox, and his three-run homer in the top of the second eventually proved crucial, since it was the Sox’ last offense of the day. Cameron also made a tremendous catch while fighting the sun in the bottom of the eighth, covering a ton of ground to haul in a Pablo Sandoval drive on the warning track while falling down.

–Darnell McDonald once again proved formidable against left-handed pitching, jumping on Giants starter Madison Bumgarner for a first-inning homer. Of McDonald’s five homers this year, four have been against southpaws.

WHAT WENT WRONG FOR THE RED SOX

–Buchholz’ departure threw a scare into the Sox, though the initial signs of his knee injury were that it was not a devastating one. Still, his early exit torched the Sox bullpen, which will be running on fumes on Sunday. The Sox are no doubt eager to arrive at Monday’s off-day.

–For the first time in his career, Daniel Nava was kept off the bases, going 0-for-3. Thus ended a run of 13 straight games reaching base to start his big league career.

–Victor Martinez, Kevin Youkilis and Adrian Beltre — the heart of the order on whom the Sox will rely even more for offense with Pedroia out — went a combined 1-for-12, a particularly surprising development given the group’s tremendous success to this point in the season against left-handed pitchers.

WHAT WAS WEIRD FOR THE RED SOX

–With the Sox dealing with a short bench and a need to pinch-hit early and often for pitchers, the team sent John Lackey to the plate in the top of the fifth to pinch-hit for fellow pitcher Ramon Ramirez. Lackey grounded out, but in the process he became the first Sox pitcher (not counting position players who took an occasional mop-up turn on the mound, or Dave McCarty, who made a few relief appearances in 2004) to pinch-hit since Pete Schourek delivered a pinch-hit single against the Orioles on June 28, 2000.

WHAT WAS A ROSTER SCRAMBLE FOR THE RED SOX

–The Sox placed Dustin Pedroia on the 15-day disabled list due to a non-displaced fracture of the navicular bone in his left foot. Pedroia said that he had no idea how long he would be sidelined for.

–With Pedroia sidelined, the Sox called up infielder Angel Sanchez from Triple-A Pawtucket to serve as a backup middle infielder.

–The Sox moved to further reinforce their middle infield depth by acquiring second baseman/outfielder Eric Patterson from the Athletics in exchange for 21-year-old left-hander Fabian Williamson. For more on that deal, click here.