With Jon Lester presumably going on the disabled list (or, at the least, missing his last start before the All-Star break), the Red Sox rotation now has just two of its original members remaining in it. Daisuke Matsuzaka was the first to go, thanks to Tommy John surgery that may have ended his Red Sox career on top of his season. Clay Buchholz is not thought to be seriously injured, but his back has been bothering him, and he isn't expected back until after the All-Star break because of it. Buchholz has been on the shelf since June 16, so this will have caused him to miss around a month's time, assuming it isn't even worse than they think.
Throw in John Lackey's struggles to be consistent this year -- his 7.47 ERA is as bloated as his chest-high fastballs on his bad nights -- and it's somewhat amazing the Red Sox sit just 1.5 games out of first place in the toughest division in the game. The rotation has been successful, but it has never been whole -- Boston just collected loads of depth this off-season, just in case, and it has paid off for them.
Tim Wakefield once again has been the team's sixth starter, making nine appearances in relief with 10 starts for 74-2/3 innings. He has not been very consistent, so you're never sure if the Wakefield who can shut down an opponent is showing up, or if it's the one that will just squeeze five innings of work and a non-quality start in, but at least he has been there when he has been needed.
Alfredo Aceves was signed so Boston could leave Felix Doubront in Pawtucket to develop, and have yet another pitcher who could work out of the bullpen, in the rotation as a spot starter, or down in the minors as necessary, as he had options remaining on his contract. He has done all of those things this year, and while he hasn't been flawless as a starter, for the seventh man in the rotation, Aceves has been everything you could hope for, especially when working in tandem with Wakefield.
Lastly, the Red Sox, since they had starters one through seven planned out, took a chance on a project pitcher, Andrew Miller. The plan was to let Miller, who had never performed like his talent and draft standing led you to believe he would, would stay in Pawtucket until he was ready to finally pitch well in the majors -- assuming that were to occur. It was a long shot, given his long standing struggles with command and being aggressive to the opposition, but something clicked for him in Pawtucket, and he has now made three starts for the big league club. Assuming Miller handles the tougher American League opponents as well as he did the NL ones, he will stick in the rotation as Matsuzaka's permanent 2011 replacement.
Those three pitchers, who were essentially signed to be the cavalry, have all contributed to the Red Sox more than was ideal already. Just because Wakefield, Aceves, and Miller can do the job isn't a good thing, as their presence means there have been problems, either from a performance or a health perspective. Plans don't always work out as expected, though, hence the need for backup plans. These three were the backup plans, and due to Boston's insistence on adding starting pitching depth to the organization despite a locked in 1-5 in the rotation, they have been able to stay in this thing despite a slew of injuries.
Throw in that their presence has allowed Doubront, Kyle Weiland, and even Miller, one of the cavalry himself, to develop in Pawtucket rather than be bounced between levels, and their value climbs higher. Even if neither Wakefield nor Aceves pitches as a starter again for the rest of the year following the latest injury troubles, they would have done their job, and done it effectively -- kudos to the front office for knowing that you can never have too much starting pitching.