After hamstring troubles, Ian Kennedy turned to his curveball

When he climbs onto the mound on Friday evening against the White Sox, Royals starter Ian Kennedy will be focused on keeping any Jose Abreu fly balls inside the confines of Kauffman Stadium. He won’t be focused on his unbeaten streak of seven games or the heatwave engulfing Kansas City.

He also won’t be thinking about how often he’s turned to his curveball. Partly because, when asked, he wasn’t even aware he’d been doing it.

“It all depends on the day,” Kennedy said. “There’s some days where it feels good, and there’s some days where you face the same team again and it might be the change-up. Last outing we threw a little less change-ups. But a few starts you sometimes start getting it going and you feel good.”

For the first time since July 2014, a month in which a mechanical change inspired him to use his curveball 18 percent of the time according to BrooksBaseball, Kennedy is using his curveball at a higher rate than his change-up. Nearly 21 percent — 20.72, exactly — of his pitches in July have been curveballs, while only 7.89 percent have been change-ups.

Throughout his career, Kennedy has turned to his fastball an average of 60 percent and his change-up 15.7 percent. He generally relies on his curveball a touch less, at 13.2 percent.

In other words, Kennedy has retooled his arsenal without really meaning to. The best explanation would seem to be the right hamstring strain he suffered in May. Upon his return from the disabled list, he struggled every time he reached for his change-up.

“It was the only pitch I would throw where I could feel (the hamstring),” Kennedy said. “Sometimes I would go into it and I’d forget about it and I’d throw a change-up and it would send, like, a zing from my knee to my groin to remind me I wasn’t fully healthy yet.”

But he didn’t have to hold onto the curveball as long. It became Kennedy’s favorite breaking pitch. He hasn’t turned back.

Even though batters are hitting .385 against Kennedy’s curve — at times taking advantage of poorly-located ones and hitting home runs, like a game-tying shot by Drew Robinson in Sunday’s game — they’re also being fooled into chasing at an above-average rate. This month, 36 percent of swings made against his curveball have been whiffs.

It’s a fun conundrum. One Kennedy isn’t too keen to solve.

“I talk to Chris Young about that. You evolve. Maybe I throw a curveball a little bit more than I have,” said Kennedy, who hasn’t won at home since Aug. 20 and is 3-0 with a 3.14 ERA over his last seven starts. “You’ve got to be unpredictable, a little bit.”

This story was originally published July 20, 2017 at 9:50 PM with the headline "After hamstring troubles, Ian Kennedy turned to his curveball."