Jonathan Papelbon is amidst a 22-inning scoreless streak. (AP)

And now, a word about the closer.

The Red Sox have suffered from inconsistency in any number of areas this year. Both individually and collectively, the team has been subject to the rhythmic ups and downs of a baseball season, mostly the stuff you’d expect from a 162-game season (Dustin Pedroia starting slowly and then getting hot; Jon Lester hitting an early bump in the road and then emerging as dominant; Jarrod Saltalamacchia and Jason Varitek seeing the pendulum swing on their seasons at the plate; etc.).

But in one area, the Red Sox have remained completely consistent from the opening bell until now. The team’s record when leading after eight inning? 74-0. Jonathan Papelbon in save situations? 30-for-31.

That isn’t to say that Papelbon hasn’t gone through his own ups and downs this season. In late May and early June, there was a stretch in which he permitted runs in five of seven outings, for instance. And in five appearances sandwiched around the All-Star break from July 5-16, he allowed runs in three different outings, lifting his ERA to 4.06 in his first game of the second half.

However, since then, Papelbon has been on what may well be the most dominant run of his storied career in Boston. In his last 21 games, he has thrown 22 innings. The results are little short of stunning.

Zero runs – tied for the longest scoreless stretch of his career.

Five hits – all singles.

Two walks.

Twenty-eight strikeouts.

Papelbon isn’t just shutting down opponents. He’s buzzing through them with the ruthlessness of a chainsaw.

On Friday night, given his first save opportunity since Aug. 18 (a 27-day stretch that ranks as the longest of his career), he operated like a man possessed, firing 12 of his 13 pitches for strikes, and working around a B.J. Upton single to punch out the side.

It has been a stretch of utter brilliance for Papelbon, who is getting swings and misses with his fastball (which has held at a tick over 95 mph all season long), splitter and slider. His fastball in particular has been an smoldering, overpowering weapon.

“He’s been awesome,” said Saltalamacchia. “His velocity has been there the whole time. The mix of his pitches has been great. And he’s hiding the ball, so it’s really tough to pick him up. He’s just been phenomenal.”

“Unbelievable,” marveled setup man Daniel Bard. “It’s the best fastball I’ve seen out of him in three years. It’s consistent. It’s every night. He just seems to get better as the season goes on.”

Yet Papelbon treats the performance in matter-of-fact fashion, as if these sorts of results are utterly unsurprising. He suggests that this is the most consistent his delivery has ever been, something that has lent itself to the most dominating stretch of his career.

“I know now what it takes to be consistent. Every year, you learn more about how to push the gas, how to hit the brake, how to prepare yourself every day and every night to repeat a delivery,” said Papelbon. “I think the consistency of my delivery has been more important than the consistency of my stuff. If my delivery is consistent, everything else should be.”

And so it has been – not only during this run, but really, throughout his Red Sox career, a fact reflected in a closing milestone he achieved on Friday. After his long wait, the closer notched his 30th win of the season, something he has now done in each of his six big league seasons. Papelbon is the only pitcher in major league history to reach that defining plateau for closers in each of his first six big league seasons.

Of course, that is in part because other great relievers – Mariano Rivera comes to mind, as does Bard – had to serve apprenticeships as setup men for full seasons before graduating to the ninth inning.

Papelbon didn’t have to wait. Instead, after a late-season callup in 2005, he found himself thrust into the job of closer in the second game of the 2006 season, and defined that as the spot where he’d spend his career by going on a run with little precedent to start his career. He reeled off one scoreless appearance after another in 2006, and in fact, had a 22-inning scoreless stretch that year from May 4 through June 26 that stood as the gold standard for the greatest run of his career – until now.

At a time when he is edging closer to the brave new world of free agency, he is dominating in a fashion reminiscent of what he did as a rookie, more than five years ago. While his 2.56 ERA this year suggests a solid performance, his 80-to-10 strikeout-to-walk ratio (the third best ratio in the majors) and 12.1 strikeouts per nine innings (fifth in the majors) suggest vintage Papelbon. And in between his overpowering first season and this one, despite some unevenness to his performance in 2010, he has remained, for the most part, great at what he does.

While saves are far from the be-all, end-all statistic by which closers should be measured, the fact that Papelbon now has reached the 30-save plateau in six straight seasons does have significance.

He has been consistent enough, and healthy enough, to claim unquestioned ownership of the ninth-inning for the Sox for almost the entirety of his big league career. And the fact that his six-year career now features bookends of dominance (his current scoreless innings streak is the longest in the majors) offers a reminder of the degree to which he has been a rock for the Sox, an area of great dependability and reliability for the Sox over a lengthy period of time.

The fact that he has reached such a milestone for six straight years is something that Papelbon values, something upon which he will reflect at some point. But for now, his focus is merely on fulfilling his role on the Sox in hopes that, by doing so, he will contribute to a much larger goal.

“[Six straight years of 30 saves]  means a lot. It does,” said Papelbon. “I’ll sit down and think about all these things after the season’s over. But for now, I’m just going out there to do my job. I know if I do my job and everybody else does their job, we can have some special things happen in this clubhouse.”