We looked at each of those pitchers from a statistical perspective (and threw in one other, Kevin Siegrist). Here’s our take on what they’ve done and what to watch for moving forward.
What’s to like:Kelly is 5-0 with a 1.79 ERA in his last seven starts, dating back to July 12. One of the keys to that has been a changeup, against which opponents have made 44 outs and allowed 12 baserunners. Opponents are 2-for-their-last 23 with two walks against that pitch.
Room for improvement: Kelly is not a strike thrower. He’s struck out 24 and walked 18 (one intentional) in 40 1/3 innings in this seven-start stretch. Within that timeframe, Kelly is getting misses on only 13 percent of the swings taken against him, the second-worst rate of any pitcher in that stretch.
What’s to like: Maness is just about as good as it gets at inducing ground balls. His ground-ball rate of 72 percent is second-best in the majors, half-a-percentage point behind Diamondbacks submariner Brad Ziegler. Maness allowed a run in his last outing, snapping a streak of 14 2/3 innings of scoreless work.
Room for improvement: Maness is very hittable. Nearly half of the swings against him have been put into play, a rate that ranks among the 10 highest in baseball. Both lefties and righties hit him equally well, combining for a .294 batting average against him.
Highest Miss Rate vs Fastball
Room for improvement: Miller has been up and down as the season has moved along. He had a 1.91 ERA in his first 12 starts this season, but a 4.06 ERA in his last 13. The primary culprit has been home runs.
He’s yielded 12 in his last 64 1/3 innings, including four in his last three starts.
RosenthalWhat’s to like: Rosenthal is among the game’s hardest throwers. His fastball averages 97.3 mph, which ranks third-best among those with at least 50 innings pitched. Only Aroldis Chapman (98 mph) and Nate Jones (97.5) throw harder. Rosenthal is using that pitch to average 12.6 strikeouts per 9 innings, sixth-best in the majors.
Room for improvement: If Rosenthal does eventually transition into the starting rotation, he’ll likely need to throw his breaking ball more. Rosenthal has thrown 72 curves and sliders this season and they’ve combined to yield eight baserunners, while netting only nine outs.
What’s to like:Siegrist currently has a 12 1/3 inning scoreless streak during which he hasn’t allowed any inherited runners to score either.
Opponents are 9-for-88 against him, with right-handed hitters being as meek (5-for-44) as lefties (4-for-44). Thus far, he’s been able to get away with throwing his fastball over the heart of the plate. He’s thrown exactly 100 heaters into the area covering the middle-third of the strike zone, width-wise and gotten 25 outs, yielding only one baserunner.
Room for improvement:Siegrist is a little wild. He’s walked 15 in 27 innings, mainly because when he throws the ball below the knees, hitters know to let it go. Of the 99 times he’s thrown a pitch to that area, he’s only gotten 10 “chases” (swings at pitches out of the strike zone), well-below the major-league average of 27 percent.
WachaWhat’s to like:Wacha had two good starts in three appearances after initially being recalled in late May. In his second stint with the team, he’s held opponents scoreless in four of five relief appearances. Wacha has shown he can get hitters out from the left side. Lefties are 12-for-59 against him with 14 strikeouts and two walks.
Room for improvement:Wacha has had three games this season in which he significantly struggled at getting right-handed hitters out. Overall, they’re 15-for-52 against him with eight extra-base hits and four walks.