His left foot caught on the mound just before he was about to stride forward to deliver a pitch to Josh Bell, a sinker that sailed well up and out of the strike zone. Then Jake Arrieta hopped awkwardly and was immediately surrounded by Joe Maddon and the training staff. Things got really ominous when he cut short a warmup toss with a scowl of pain twisting his face.
Arrieta walked off the mound with a noticeable limp, supported by trainer Ed Halbur as he headed back to the clubhouse. Given the nature of hamstring injuries, many feared they’d seen the last of the former Cy Young winner this season.