Cole Hamels was dominating opponents with fastballs just before an oblique injury sidelined him on June 28. Since returning a little over a month later, however, Hamels has thrown slower and has surrendered a 7.29 ERA.
Hamels’ fastball has averaged 91 mph since being activated from the injured list, which is down from his typical 91.8-92.5 mph range from March through June.
That decreased velocity has coincided with his highest isolated power (ISO) against of the season. Hamels has allowed a .474 ISO on his fastball in August, a significant departure from the .070 he allowed in June.
It’s possible that Hamels is still working his way back from his injury and that we’ll see his velocity steadily increase as he gets his mechanics dialed back in. However, time is his enemy, as he only has around a handful of starts left in the regular season.