If you’ve been around these parts for the past six months or so, you’re already aware of my stance on ERA for relief pitchers and how generally useless I think the stat is. The long and short of it is that on many occasions throughout the year, a reliever will enter the game with runners already on base. Those runners aren’t the responsibility of the reliever, statistically speaking, as if they score the runs are charged to the record of the pitcher who allowed them to reach base.
Of course, some managers are less likely to put their relievers into this situation that others. Mike Scioscia of the Angels brought relievers into a game with runners already on base a league-low 89 times last season while Joe Maddon (ironically a Scioscia disciple) brought his Rays relievers into a game with runners on the bases a league-high 176 times. Note that these numbers don’t simply include the first reliever of the game, but all subsequent hurlers as well. Obviously, Scioscia prefers to allow his pitchers to start an inning fresh while other managers are more willing to let a pitcher get himself into trouble before removing him from the contest. Managers that employ “specialist” relievers who will be used to be one or two batters at most will usually see a higher number here.
Jim Leyland’s Tigers club was closer to the high end as their relievers inherited runners in 156 games, the fourth most in the league. The key factor in determining how effective the relievers are, in my mind, is how often those relievers can escape the trouble and prevent the inherited baserunners from becoming earned runs charged to the previous hurler. Again, if Joel Zumaya comes in with two runners on base and records two outs to end the inning, but along the way gives up a double that scores those runners, Zumaya’s ERA for the outing is 0.00, but the guy who put those runners on base gets hit with a higher ERA.
Whether you come into the game with runners on base or not, up four runs or down by six, the job of the pitcher is keep any runs from scoring, whether they be his “responsibility” or not. When judging how effective your bullpen is, you need to look beyond ERA and also look at how often a pitcher was able to keep those runners from scoring, because ultimately that’s what will tell the tale of how good or bad his outing was.
Not only did the Tigers frequently bring pitchers into games with runners already on base, but there were a total of 250 runners inherited, which is twenty more than the average AL club but basically middle of the pack in terms of rankings. The Tigers relievers allowed 94 of those 250 runners to score, or 38 percent. Those 94 inherited runners that wound up on someone else’s ERA are the most of any AL ballclub. And that 38% scoring rate is second-worst behind only Kansas City.
Detroit did a little to address the problem this winter by adding right hander Joaquin Benoit to the bullpen. Benoit inherited 23 runners last season for Maddon’s Tampa Bay club and allowed only two of them to score (9%). This shows that his impressive ERA wasn’t merely a technicality, but that he was proficient at keeping all runs from scoring, his responsibility or not. The addition of Benoit and subtraction of Eddie Bonine should go a long way toward eliminating this problem in 2011. Bonine allowed a whopping 61 percent of his inherited runners to score (17 of 28 runners).
By and large, Tigers relievers were actually okay at stranding inherited runners, but the bad ones were very, very bad.
As you can see from the above, the pitchers generally considered to be the better arms are also the best at keeping inherited runners from scoring. I was surprised to see that Perry, despite his general inconsistency last season, was the best the Tigers had to offer at quashing a rally. Conversely, Brad Thomas was far more effective at keeping his own runners from scoring than he was at stranding inherited runners.
The addition of Benoit will not only give the Tigers a dominating force in the set-up role, but will push Zumaya and Perry into the earlier innings. This will help to eliminate the need to use a guy like Thomas in situations where his propensity to allow inherited runners to score can hurt the team. Instead of using Thomas when the starter gets in trouble in the fifth or sixth, now Leyland can go to Zumaya or Perry for an inning and still have the rest of the late-inning relievers in line to close the game.
Theoretically, moving Coke to the rotation and essentially replacing him with Schlereth should help as well. But Schlereth has such a small sample size that it’s impossible to guess how well he’ll strand inherited runners this year.
The Tigers bullpen allowed 24 more inherited runs to score last year than the average AL club while the White Sox and Twins were among the best at preventing those runners from scoring. If Detroit plans on winning this division in 2011, the relievers had better bring the hose to put out a fire much more often. As a unit last year, they seemed to prefer the gas can.