Karns did not have many appearances this season due to a forearm strain, but before hitting the IL he had a bit of a hard time with his changeup control as he walked a batter and hit one in four plate appearances.
Karns saw his curveball usage drop by 50% from what it was his previous full season in 2017, which can possibly be attributed to the discomfort he was feeling in his arm as he eventually missed the rest of the season due to a forearm strain. The curve has always been his strikeout pitch seeing as it was the one that accumulated the most punchouts in every season of his career.
The forearm strain that caused Karns to miss the entire season could be to blame for the drop in velocity of his fastball by more than 2 mph. He’ll look to regain that velocity if he ends up pitching again, since he cannot afford to keep it that low considering the lack of success he’s had with it in the past (wOBA over .376 in his previous three seasons prior to 2019).
Karns gets above-average rise on his four-seamer, with good velocity, but struggled badly to miss bats with it. The rise doesn’t play up when you throw it in the middle of the zone and down like Karns does, and hitters made him pay, batting .328 with an insane .414 ISO against the pitch. Karns also mixed in a sinker 59 times, with similar results.
Historically Karns’s strongest pitch, the curveball stayed true to form in 2017 despite a loss of movement. Karns threw the pitch hard, and racked up a ton of whiffs with it, thanks in part to a 49.1% chase rate and 53.1% contact rate. It managed contact well too, producing 60% grounders and limiting hitters to a .167 average and .097 ISO.
Karns bumped up his change-up usage in 2017, and it proved to be a useful pitch for him. The pitch gets above-average armside run, and roughly average drop. He controlled it well, throwing it in the zone a bit more than average, and getting good whiffs with it. It produced a 65% groundball rate, and held opponents to a .192 average.