With an 8-10 record and 4.98 ERA after 28 starts, Lester is having the worst season of his seven-year major league career. But he appears to be turning himself around in recent starts.
In his past three appearances, Lester has allowed five runs and 14 hits over 20 innings. He's struck out 22 batters during that span while walking eight. Lester told the Boston Herald's Michael Silverman that the difference has been in his pitch selection and a more aggressive approach.
Continuing that process through September will be a major encouragement, assuring the Red Sox that they'll have an ace at the top of their rotation next season.
Buchholz has been Boston's most consistent starter, compiling an 11-4 record and 4.47 ERA in 22 starts.
That ERA would seem to indicate that Buchholz still has some improvements to make. But that number is inflated due to his first-half struggles.
During the second half, Buchholz has been much more consistent, compiling a 2.91 ERA in eight starts. As Evan Brunell wrote for ESPN.com, the difference for Buchholz has been establishing his changeup. He can throw the pitch for strikes, giving him a five-pitch arsenal.
Perhaps the most pleasant surprise for the Red Sox this year has been the emergence of Doubront, who gave the rotation a strong left-handed starter while Lester struggled through most of the season.
In 23 starts, Doubront has a 10-6 record and 4.79 ERA. He hasn't pitched as well recently, giving up four or more runs in four of his past five starts. But a left knee injury put him on the disabled list for most of August.
The real problem with Doubront may be fatigue. He's pitched 127.1 innings this season, far more than the 87.2 he logged between the minors and majors last year. Scott Lauber of the Boston Herald reported that the Red Sox may shut him down after 150 innings.
Though he's struggled in his past two appearances, Morales has generally been impressive in nine starts for the Red Sox this season. (He's appeared in 37 games overall.)
He's compiled a 3-4 record and 3.77 ERA with 76 strikeouts in 76.1 innings. His rate of 9.0 strikeouts per game is one of the best on the Red Sox pitching staff.
Manager Bobby Valentine told WEEI.com's Stephen Hewitt that he likes Morales as a starter and prefers him in that role. Morales wants to start as well. Unless the bullpen is short-handed next year, there seems to be no reason not to keep Morales in the rotation.
The Red Sox need a fifth starter next season. They could add an innings-eater like Joe Blanton to the back end of their rotation or take a chance on someone like Joe Saunders. But why not sign someone with some potential upside?
Santana has a $13 million option with the Los Angeles Angels for next season, but the Angels will probably opt for a $1 million buyout instead.
Santana has had a miserable 2012 season, posting a 7-11 record and 5.45 ERA. But he's capable of pitching 200 innings and striking out seven batters per game. Leaving the pitcher-friendly Angel Stadium for Fenway Park could be a concern, however.