2015 Relief Pitcher Ball-in-Play Retrospective – AL
Over the last few weeks in this space, we’ve conducted a ball-in-play based analysis of position players’ and starting pitchers’ 2015 performance, the most recent post featuring an examination of starting pitchers in the AL West. Next, we’ll take a similar look at relief pitchers. It’s admittedly a little dicey to evaluate relief pitchers in this manner. The sample sizes are much smaller, and filled with more noise. Still, it’s a worthwhile exercise that can show us the different manners in which closers, set-up men, et al, get it done.
First, some background on the process. I identified the 214 relief pitchers from both leagues who yielded the most batted balls in 2015, making sure that all team save leaders were included in the sample. From that group, I selected 28 pitchers from each league for further scrutiny. Pitchers are listed with their 2015 league mates; those who were traded during the season will appear in the division in which they compiled the most innings. Pitchers are listed in “tru” ERA order. For those who have not read my previous articles on the topic, “tru” ERA is the ERA pitchers “should” have compiled based on the actual BIP frequency and authority they allowed relative to the league. Here we go:
| AVG MPH | FB/LD MPH | GB MPH | POP% | FLY % | LD% | GB% | ADJ C | K% | BB% | ERA- | FIP- | TRU- | |
| A.Miller | 86.13 | 86.66 | 86.31 | 3.3% | 30.0% | 18.3% | 48.3% | 80 | 40.7% | 8.1% | 50 | 51 | 44 |
| Uehara | 85.92 | 88.23 | 80.50 | 9.0% | 47.0% | 17.0% | 27.0% | 59 | 29.4% | 5.6% | 53 | 61 | 44 |
| O’Day | 84.88 | 85.89 | 86.60 | 5.2% | 39.6% | 20.1% | 35.1% | 67 | 31.9% | 5.5% | 37 | 59 | 45 |
| Britton | 89.93 | 94.83 | 87.93 | 0.0% | 9.5% | 11.4% | 79.1% | 71 | 31.2% | 5.5% | 47 | 48 | 49 |
| Fields | 88.18 | 91.81 | 83.06 | 6.7% | 40.9% | 18.3% | 34.2% | 64 | 32.1% | 9.1% | 88 | 53 | 50 |
| C.Smith | 88.08 | 88.75 | 88.45 | 1.3% | 16.9% | 17.0% | 64.8% | 75 | 32.4% | 7.8% | 60 | 54 | 52 |
| Cecil | 87.86 | 88.76 | 86.94 | 4.0% | 25.4% | 19.0% | 51.6% | 82 | 32.7% | 6.1% | 61 | 57 | 54 |
| W.Davis | 85.18 | 90.24 | 80.41 | 4.6% | 36.5% | 20.5% | 38.4% | 74 | 31.1% | 8.0% | 23 | 57 | 55 |
| Gregerson | 86.85 | 92.75 | 84.31 | 2.4% | 20.8% | 16.5% | 60.4% | 71 | 24.7% | 4.2% | 77 | 69 | 56 |
| Street | 86.82 | 89.33 | 83.15 | 1.7% | 43.7% | 20.1% | 34.5% | 58 | 22.4% | 7.8% | 83 | 95 | 57 |
| Betances | 84.04 | 90.25 | 81.07 | 3.9% | 27.7% | 20.6% | 47.7% | 93 | 39.5% | 12.1% | 37 | 59 | 58 |
| Lowe | 87.91 | 90.47 | 84.78 | 2.9% | 29.5% | 27.3% | 40.3% | 83 | 28.4% | 5.6% | 49 | 64 | 61 |
| C.Allen | 87.93 | 89.00 | 88.38 | 6.3% | 34.8% | 25.9% | 32.9% | 94 | 34.6% | 8.7% | 75 | 45 | 62 |
| Kela | 88.81 | 91.16 | 88.66 | 3.8% | 25.0% | 20.5% | 50.6% | 80 | 28.0% | 7.4% | 56 | 63 | 63 |
| Madson | 88.77 | 93.94 | 85.13 | 2.3% | 29.3% | 13.5% | 55.0% | 75 | 23.4% | 5.7% | 53 | 77 | 63 |
| Soria | 86.84 | 88.47 | 84.76 | 2.7% | 32.5% | 22.5% | 42.3% | 72 | 23.5% | 7.0% | 64 | 93 | 64 |
| Hendriks | 90.45 | 91.23 | 89.74 | 3.9% | 27.2% | 22.6% | 46.3% | 96 | 27.2% | 4.2% | 72 | 52 | 69 |
| Osuna | 88.18 | 88.96 | 88.26 | 3.9% | 42.2% | 19.7% | 34.3% | 93 | 27.7% | 5.9% | 63 | 73 | 69 |
| Robertson | 89.46 | 92.66 | 88.08 | 3.4% | 30.8% | 30.2% | 35.6% | 120 | 34.4% | 5.2% | 84 | 60 | 70 |
| Perkins | 91.34 | 92.18 | 93.14 | 5.2% | 39.6% | 21.5% | 33.7% | 89 | 22.7% | 4.2% | 82 | 94 | 73 |
| Rodney | 84.74 | 89.98 | 81.48 | 3.9% | 27.6% | 18.0% | 50.6% | 75 | 20.9% | 10.5% | 123 | 125 | 76 |
| W.Harris | 87.14 | 90.38 | 84.41 | 1.1% | 28.6% | 19.8% | 50.5% | 91 | 24.6% | 8.0% | 47 | 89 | 77 |
| Herrera | 85.85 | 91.13 | 83.02 | 1.0% | 31.6% | 22.6% | 44.7% | 84 | 22.4% | 9.1% | 67 | 86 | 79 |
| G.Holland | 87.30 | 91.08 | 84.12 | 6.1% | 22.8% | 21.9% | 49.1% | 81 | 25.4% | 13.5% | 94 | 82 | 80 |
| Tolleson | 88.15 | 91.56 | 84.06 | 4.5% | 32.4% | 20.7% | 42.4% | 103 | 25.5% | 5.7% | 70 | 83 | 80 |
| Boxberger | 86.59 | 88.75 | 85.30 | 5.6% | 36.9% | 21.3% | 36.3% | 102 | 27.3% | 11.8% | 96 | 108 | 87 |
| J.Smith | 90.61 | 92.96 | 89.29 | 1.6% | 23.1% | 23.2% | 52.1% | 101 | 21.0% | 7.0% | 94 | 81 | 90 |
| Petricka | 86.53 | 90.71 | 85.59 | 0.0% | 17.1% | 17.7% | 65.2% | 91 | 15.0% | 8.2% | 89 | 83 | 97 |
First, a little background. The larger group of 214 relievers had a cumulative strikeout rate of 22.2% and walk rate of 8.2%. Both rates are higher than the comparable marks for starters (19.8% and 7.0%, respectively). The larger group of relievers also conceded less authoritative contact than starters, allowing lesser overall (88.02 mph for relievers, 88.46 mph for starters), FLY/LD (91.24 vs. 91.78) and grounder (85.76 vs. 86.30) authority. With regard to BIP frequency, relievers outpaced starters in the key grounder rate category by 45.6% to 45.2%, and matched them in pop-up rate (3.2%).
The subset of relievers listed above generally represents the cream of the relief crop. Most of the column headers are self-explanatory, including average BIP speed (overall and by BIP type), BIP type frequency, K and BB rates, and traditional ERA-, FIP-, and “tru” ERA-. Each pitcher’s Adjusted Contact Score (ADJ C) is also listed. Again, for those of you who have not read my articles on the topic, Unadjusted Contact Score is derived by removing Ks and BBs from opposing hitters’ batting lines, assigning run values to all other events, and comparing them to a league average of 100. Adjusted Contact Score applies league-average production to each pitchers’ individual actual BIP type and velocity mix, and compares it to league average of 100.
