The Detroit Tigers should have seen it coming from a mile away. Instead, they ignored the signs that Jordan Zimmermann was not ready to return from the disabled list, and paid the price in an embarrassing 11-3 loss on Saturday. Zimmermann allowed six runs and recorded just three outs before leaving the game, and the Tigers never recovered in a game with serious AL playoff implications.
The worst part? The Tigers have been here before. Zimmermann’s previous attempt at a return from injury ended just as poorly, with six runs allowed in 1 2⁄3 innings against the Chicago White Sox on August 4. If you include his five minor league rehab starts between the two injuries, Zimmermann has allowed 22 runs (15 earned) in 23 innings since the All-Star break.
Luckily, they might be learning from their mistake. Tigers manager Brad Ausmus was non-committal about Zimmermann when talking to reporters after Saturday’s game. On Sunday, Ausmus announced that Zimmermann would throw a simulated game on Wednesday instead of making his scheduled start on Thursday against the Minnesota Twins. With Michael Fulmer set to start against the Cleveland Indians this weekend, Mike Pelfrey looks like the most likely option to start on Thursday.
The decision to skip Zimmermann’s start comes as a bit of a surprise given the Tigers’ recent history. They continued to rely on Anibal Sanchez earlier this season when his performance was actively hurting the team, and were quick to throw Zimmerman back into the rotation in August in his previous attempt at returning from injury.
Zimmermann and the Tigers have both insisted that he is healthy, but his performance says otherwise. He walked three batters and did not record a strikeout on Saturday, and has just one start with more than three strikeouts in his last nine major league outings.
Worse yet, Zimmermann’s velocity has continued to decline. He averaged 93.4 miles per hour on his four-seam fastball in 2015 (down from 94.6 mph the year prior), and that figure has declined to 92.6 mph in 2016. He has been even worse lately, averaging just 91.96 miles per hour with the four-seamer in his last four starts. His fastest heater hit just 93.1 mph on Saturday, which was lower than his average fastball in 2015.
Zimmermann’s off-speed pitches haven’t been as sharp, either. His slider velocity has only dipped by about half a mile per hour since 2014, but the movement has tailed off significantly in 2016. His best slider has good two-plane movement, breaking down-and-away from right-handed hitters. This season, that vertical movement has dropped off, leaving his slider much flatter and more hittable than ever before.
Opponents are hitting just .233 off Zimmermann’s slider this season, but are slugging a healthy .387. That .153 isolated power (ISO) against his slider is much higher than in 2014 (.043) and 2015 (.069).
Whatever the reason for this drop-off in production, Zimmermann’s stuff and production are not good enough for the Tigers to start right now. Detroit has gotten by with young lefties Daniel Norris and Matt Boyd in the rotation thus far. They are out-performing Zimmermann, and deserve the chance to carry this team to the postseason. Until they can be sure that Zimmermann’s stuff rebounds to pre-injury levels, the Tigers are better off leaving their $110 million man on the sidelines for now.