White Sox relief pitcher Tommy Kahnle delivers to the Tigers in the ninth inning at Guaranteed Rate Field on Thursday, April 6, 2017. (Chris Sweda / Chicago Tribune)
When the White Sox called up Tommy Kahnle in the first week of the season, pitching coach Don Cooper declared the right-handed reliever had an arm that “doesn’t belong in the minor leagues.”
Kahnle, who didn’t make the team out of spring but was summoned after Jake Petricka strained his right lat, has made good on Cooper’s words over his 10 appearances.
Entering Sunday’s game against the Tigers, Kahnle allowed one earned run on six hits with one walk and 19 strikeouts in nine innings pitched. With a fastball that is averaging 98 mph, according to MLB.com, he leads American League relievers in strikeouts per nine innings pitched and ranks fourth in strikeouts.
Kahnle, 27 said he likely has never had such a stretch before in the majors, and he credited mechanical adjustments with helping his fastball command.
“It’s just a few mechanical changes, one with the leg kick and keeping my head on a straight line,” Kahnle said. “That’s basically keeping me going toward home plate and keeping my fastball command right there. It’s just a little more focused probably as well.
“(The leg kick) is basically just modified so I don’t sway back or take too long with my arm action. That way I’m opening up. But now I’m more closed with a direct line to the catcher.”
Kahnle pitched in 90 games in two seasons with the Rockies before the Sox picked him up via trade for minor-league pitcher Yency Almonte before the 2016 season.
Sox manager Rick Renteria said Kahnle began to make improvements late last year.
As he bounced back and forth from Triple-A Charlotte early in the year, he posted a 3.71 ERA with 16 walks and 14 strikeouts through August. Then in 11 September games, he posted an 0.87 ERA with four walks and 11 strikeouts.
“His confidence level is obviously growing but I think it’s commanding the zone,” Renteria said. “He’s staying down in the zone, throwing a lot of strikes. He’s mixing in his slider, which has been very effective. He’s throwing a lot of strikes and the velocity doesn’t hurt.”
Kahnle’s success has helped the Sox bullpen post a 1.99 ERA, best in the majors.
He didn’t have a great spring, but he felt he clicked during a simulated game in Charlotte before the call from the Sox.
“It really has taken off from there,” Kahnle said.