This is why the Red Sox stockpiled a pitching surplus.

Daisuke Matsuzaka is 1-5 with an 8.52 ERA. He has looked lost on the mound for nearly all of a season in which he still has yet to deliver a single quality start.

Ultimately, after he lasted just four innings and allowed six runs on Friday, the Sox had little choice but to pull the plug. The team announced that, rather than going with a six-man rotation with the impending return of John Smoltz, Matsuzaka’s next scheduled start will be skipped.

Matsuzaka was examined at length on Saturday by the team’s medical and training staff. He underwent an MRI that showed no structural damage. Even so, in all likelihood, the pitcher will end up on the disabled list after Monday to address what manager Terry Francona called “some weakness” in his shoulder -- the same issue that had him on the D.L. for much of April and May.

“We’ve been fighting this (shoulder weakness) all year. It’s been hard, and I know that I keep coming back to the (World Baseball Classic), and that’s probably not a real popular thing in baseball to say that, but (Matsuzaka) didn’t have a chance to get a foundation (for his arm strength),” said Francona. “You’re ramped up to try to get people out probably before he was ready. Physically it’s happened to pitchers where they’re pitching in earnest before their bodies or arms are ready to do that, and I think we paid the price for that.

“We’ve been playing catch-up,” Francona continued. “We did what we thought was right to shut him down earlier (this year, when he went on the disabled list in April). I think we all see that it’s not really getting strong or better. It’s been a struggle so we’re trying to address that.”

It is a remarkable commentary on the 2009 Red Sox that Matsuzaka’s removal from the rotation -- for however long -- seems more like a solution than a problem. Most teams would be sent into panic mode if a pitcher who had won 18 games a year ago landed on the sidelines.

The Sox, however, seem perfectly comfortable with the fact that, rather than featuring a six-man rotation, the team will instead feature a group that includes four pitchers -- Josh Beckett, Jon Lester, Brad Penny and Tim Wakefield -- that is pitching its best baseball of the year, and that will now be joined by a future Hall of Famer in John Smoltz.

Because of their depth, the Sox have the luxury of removing a struggling and/or injured pitcher and give him time to rediscover what made him good. Instead of paying a premium in the trade market -- having to buy pitching at a time of year when it is most expensive -- the team is able to find its answers from within thanks to the winter acquisitions of Penny and Smoltz.

In effect, the Sox made their trading deadline acquisitions to address an area of need in December and January. As a result, there is no sense around the club that Matsuzaka’s struggles or his removal from the rotation will hinder the first-place club.

“Pitching depth is valuable all the time,” said catcher Jason Varitek. “It shows how smart [G.M. Theo Epstein and the front office] are. Give them their due.”

“Everyone wants options,” added Smoltz. “It’s a unique opportunity that (the Sox) created way back in the offseason. It’s played out in a way that is the best worst-case scenario you can have.”

Here are four other lessons absorbed on night when Josh Beckett and the Sox beat the Braves, 3-0, in Derek Lowe’s return to Fenway Park (recap here):

JOSH BECKETT DOES NOT PRESENT A WELCOME MAT TO RETURNING SOX

Woe betide the former Sox pitcher who must make his return to Fenway Park against Josh Beckett.

In 2006, it was Pedro Martinez who stepped into the spotlight at Fenway as a member of the Mets. The three-time Cy Young winner was shelled, while Beckett, his counterpart, dominated the evening, going 7.2 innings and allowing just two earned runs.

On Saturday, it was Derek Lowe’s turn. Lowe was in vintage form. But the sinkerballer’s fine outing (6.1 innings, 3 runs, 7 hits) was not good enough against a dazzling Beckett, who once again significantly outpitched a former Sox hurler.

There are pitchers who are described as having no-hit stuff every time they take the mound. Beckett continued to take that expression to something of an extreme in beating the former Red Sox 20-game winner.

Beckett needed just 94 pitches to deliver his first complete-game shutout as a member of the Red Sox (the third of his career). His ability to command a powerful mid-90s fastball, a nasty two-seamer that helped him to a Lowe-like 12-7 groundout-to-flyout rate, and one of his finest changeups of the season allowed him to overpower the Braves for most of the night.

“They were aggressive and put some balls in play early in the count,” said Varitek. “That’s big for a power pitcher like Josh.”

As Beckett kept posting zeros, it became clear that his poor outing last Sunday against the Phillies (six innings, seven runs, six earned, 11 hits) was an aberration. In his last eight starts, opponents are hitting just .184 against Beckett. 

The last time that a Sox starter threw a complete-game shutout with that few pitches was on August 18, 1993, when Danny Darwin also needed 94 pitches to accomplish the feat against the White Sox.

Beckett retired 11 straight batters from the fourth through seventh innings before running into his lone jam of the night by allowing a pair of hits in the eighth. With one out and runners on first and second, he fell behind Jeff Francoeur, 2-0 and then 3-1.

But Beckett unleashed a 96 mph sinker that Francoeur hit back up the middle. Beckett fielded the ball cleanly and fired a perfect lead throw to second to commence a 1-6-3 double play and shut down the jam. He then needed just five pitches to sail through the ninth to conclude his first shutout since 2005.

“On a really aggressive team, he established his fastball in and out,” said Francona. “He did everything. He was economical. That was fun to watch.”

DEREK LOWE MADE IT SEEM AS IF FIVE YEARS WAS NOT SO LONG AGO

In some ways, it is hard to believe that five years had passed since Derek Lowe had last been on the pitching mound at Fenway Park. Certainly, the sinkerballer’s stuff did not resemble that of a pitcher five years removed from contributing to a World Series in 2004.

“D-Lowe’s 36 already? He looked good. It’s been a while,” said Ortiz. “(But) it doesn’t feel like a long time.”

Lowe pumped his sinker across the plate in the low-90s, exhibiting as much power -- perhaps more, at times -- as he did when with Boston. While he mixed in some breaking pitches, for the most part, he was the same pitcher who won 72 games as a member of the Red Sox.

“He really did a good job of keeping the ball down … and down and down,” said Sox catcher Jason Varitek, who spent 10 years as Lowe’s teammate in the minors in both the Seattle and Boston systems and with the Sox. “He threw the ball really well.”

“That’s the guy we’ve seen so much,” said Francona. “When it’s down, there’s not a lot you can do with it. Even when you know what’s coming it’s hard to get (the ball) in the air…He was the guy we remembered when he was going good.”

That, perhaps, made it all the easier for the crowd at Fenway to give him repeated and sustained ovations. Lowe received a standing round of applause from the fans around the visitor’s dugout when he made his way there from the bullpen before the start of the game.

Then, after 6.1 solid innings in which he allowed three runs on seven hits and recorded 12 groundball outs, the entire park rose in a gesture of appreciation for the former All-Star’s contributions as a Red Sox.

The memories of those times -- including his no-hitter, a 21-win season, and key contributions in the clinching game of the 2003 ALDS (a save against the A’s) and the clinchers in all three playoff series in 2004 -- were near at hand. Though Lowe was out-pitched by Beckett and faced a night of significant emotions, he more than held his own.

“Playoff games are all about how fast you can settle down because you’re going to have all the emotions going,” said Lowe. “It wasn’t to that degree, but it was more than just another game because of all the years I spent here. I enjoyed pitching here.”

JASON VARITEK KNOWS HOW TO HIT A SINKER

As recently as June 6, Jason Varitek was hitting .250 with an .863 OPS. But in the subsequent two weeks, he had been in a deep rut.

Varitek had entered last night hitting .040 (1-for-25) with a .306 OPS in his previous eight games. And so it seemed an event worth noting that he had his first multi-hit game in the month of June, driving a pair of doubles to left-center against Lowe, his longtime batterymate.

“We had talked about the approach you wanted to have off of Lowe,” said hitting coach Dave Magadan. “What you need to do against him is get the ball up, stay inside it and hit it the other way. Tek did it to a tee. The two doubles that he had was textbook how you want to hit Lowe.”

Magadan said that, despite the recent slump, Varitek continues to have good at-bats from both sides of the plate. He also said that while the Sox captain’s simplified mechanics as a left-handed hitter are sometimes a challenge to maintain, that by and large, Varitek has been able to do so, and that in the long run, he will be rewarded for that effort.

“I know he’s been a little frustrated because the results aren’t there,” said Magadan. “But I think if he stays with it, stays with what he’s doing, the numbers will be better than what they’ve been in the past at the end of the year.”

Varitek’s two doubles gave him 281 in his career, breaking a tie with Nomar Garciaparra for sole possession of eighth place in Red Sox history.

NICK GREEN’S CONTRIBUTIONS CONTINUE TO EXCEED ANY POSSIBLE EXPECTATION

The top and heart of the Red Sox lineup could do little against Derek Lowe. And so it was the bottom of the order where the team did its damage.

Varitek’s two doubles were huge, but ultimately would have been meaningless but for Nick Green’s night. Green followed both of Varitek’s doubles with hits of his own – a run-scoring double in the fifth, and a hard single in the seventh that moved Varitek to third and set up the third Red Sox run.

On the year, Green is now hitting .292 with a .783 OPS. In his last 11 contests, he is hitting .361 with three doubles and two homers. Green ranks sixth among A.L. shortstops (minimum 150 plate appearances) in average and fourth in OPS.

As a result, the Sox have fulfilled the preseason expectations of their shortstop depth, only it has been the result of an entirely unexpected contributor rather than the combination of Jed Lowrie and Julio Lugo.