Alfredo Aceves has been excellent in 2012. Alfredo Aceves has also been awful this year. He's blown more saves than anyone else, and while some of those appearances gone awry have had a lot to do with inheriting too many runners, there have been plenty of occasions where the damage was all on Aceves. The right-hander has allowed 32 runs on the year, with more than half of those coming in just four appearances: five runs against the Yankees on April 21, five against the Angels just last week, four against the Twins on August 4, and three to the Tigers back on April 8, in the season's second contest.
Aceves has lost eight games, and while those might not be all on him, as the guy who comes in late in the game to close things out, there's more of those Ls on him than you can say for a starting pitcher, who is a bit more reliant on his offense to provide support. Aceves, on the other hand, is entering a game at its nearly completed state, and as such is doing his job if he's not racking up decisions.
Let's not boil his season down to wins, losses, and blown saves, though. While Aceves has been terrible when he's been off, between those 17 runs in four contests and another four appearances with two runs allowed, Aceves has also had stretches where he's been flat-out awesome. From April 23 through July 29, Aceves threw 50 innings in 43 games, holding opponents to a .205/.273/.284 line with a 2.9 K/BB and just three homers allowed. For this, he posted a 2.34 ERA, besting the work from his impressive 2011 in this stretch.
August has been rough like April was, though, with Aceves posting a 10.34 ERA this month thanks to four homers and 11 earned runs in under 10 innings. Stretches like this make it difficult to rely on him as the closer, and since there have now been two of them rather than just the one, it's fair to start wondering if this is the role for him.
On a team without Andrew Bailey around, you might keep Aceves in the role to see if he can work out the kinks. But, Bailey is on the Red Sox, and was acquired to close in the first place -- Aceves was keeping that seat warm until Bailey returned from injury. Now, Boston knows they have a guy who can fill in for Bailey if he's injured in the future, but that doesn't mean he needs to hold on to the job in the meantime.
Plus, Aceves has been a more consistent -- and arguably more useful hurler -- when not in a defined bullpen role. He threw 114 innings in 2011, splitting time between mop-up, spot-starting, and high-leverage relief frames. He was something of a super reliever, in that he could be used often, and for long stretches of time, and in just about any role he was needed in. There's huge value in that -- Aceves finished third on the 2011 Red Sox in wins above replacement among pitchers, besting closer Jonathan Papelbon's total by more than a win.
Why couldn't Aceves replicate that in 2012, as the team's closer? Fewer innings, for one: Aceves pitched in 55 games in 2011, totaling 114 innings, whereas in 2012 he has appeared in 58 contests and thrown 62-2/3 innings. As the difference between Papelbon and Aceves from 2011 shows, the inherent higher leverage of the ninth can't beat out so many innings of quality pitching easily.
More importantly, though, at least in terms of who Aceves is in 2012 compared to 2011, is how he pitched. Aceves focused more on his velocity as closer, throwing in the mid-90s (and touching the high-90s often), whereas he paced himself more in the past, when he averaged 93 mph as he has for his entire career. His sinker and cutter also saw similar bumps in velocity, but his curve and change-up remained at their respective speeds.
In many ways, this jump in pitch speed has worked out. Aceves is striking out 8.2 batters per nine, nearly two whole hitters more per nine than he did in 2011 and in his career before 2012. When he's been on, as shown above, he's been phenomenal. But there are issues here that didn't exist in his past. Aceves still has roughly the same control he did, but his command isn't quite as good as it was at lower speeds. Missing his spots has resulted in more hard-hit balls from the opposition, and it's also forced him to throw some hitter's pitchers in hitter's counts. Because of this, his split-adjusted OPS+ with the batter ahead has jumped from 2011's 80 (.246/.436/.426) to 127 (.273/.515/.591) in 2012.
While he's still been better than average in an even count, he's also had issues there, with his sOPS+ jumping from 58 to 92. His ground ball percentage dipped slightly, his homer rate nearly doubled, and his pitches per plate appearance went from 3.7 to 3.9. That might not seem like much, but over the course of 474 batters faced (his 2011 total), that's a difference of about 100 pitches -- more chances for mistakes, more opportunities for hitters to walk or find their pitch to drive.
Remember, too, that his 2011 numbers are slightly depressed by his time as a starter. He struck out as many as he walked in four starts and 21 innings in the rotation, whereas while relieving, Aceves posted a 2.03 ERA and 2.3 K/BB in 93 frames. When he's used often, his command is far better, and he becomes a force in the bullpen. When starting, and maybe when closing, too, he just doesn't get the consistent work his arm can not only handle, but possibly requires, in order to be at his best.
Aceves is unlikely to be Boston's closer going forward, and not just because of the tantrum that earned him a three-game suspension from the team. He was a temporary solution that, given the circumstances, worked out for Boston. Those circumstances have changed, though, and Boston can now attempt to get their super reliever back in the role that's best for both parties.
PITCHf/x data courtesy of Brooks Baseball