Orion Kerkering is eager to test out a new pitch following his return from a minor strain

CLEARWATER, Fla. — Orion Kerkering couldn’t wait to get back on the mound.

The 24-year-old right-hander threw his first bullpen session in over two weeks on Saturday, after a mild hamstring strain had slowed his start to the spring. Part of the reason Kerkering had been so impatient throughout the rehab process was because he had been toying with a new splitter, and he wanted to get back to working on it.

Kerkering said he felt good coming out of the session, and thought his velocity was where he wanted it to be for the first outing. And he liked the shapes of the splitters that he threw.

“I think it’s a work in progress still, but I think consistently we’re getting a lot better each day with it,” Kerkering said.

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Initially, Kerkering believed he had a charley horse when he felt something in his hamstring during a bullpen session last month, before camp had officially opened. He thought he could power through it, but knew something wasn’t right when he tried to run. That meant shutting down for a few weeks.

But now, he’s back on the mound, which means he’s one step closer to testing out his new pitch against hitters. This offseason, he had discussed with pitching coach Caleb Cotham the possibility of adding something to his repertoire of four-seam, two-seam, and sweeper.

“Give the hitters more, ‘Oh [expletive], there’s another fourth pitch here that I have to look for,’” Kerkering said.

He briefly considered a cutter, before deciding on the splitter for another weapon against lefties, one that Kerkering hopes will get more of a swing-and-miss.

“It’s just another look,” said manager Rob Thomson. “He’s got a two-seam, got riding. He’s got a ball going this way with the slider. Now you got a ball going straight down, if he can master it. But he’s working on it, anyway.”

The pitch is still in its early stages, and he’s still toying with the grip. Kerkering watched videos of Mariners pitcher Logan Gilbert and other pitchers on YouTube breaking down their splitter grips over the offseason to get some ideas.

His next bullpen session is scheduled for Tuesday, and he plans to ask a hitter to stand in the box while he’s throwing to get their point of view.

“If they can see the difference in me trying to grab the grip,” Kerkering said. “... I think just overall, just see what the hitters see. And I think that’s my best feedback on that pitch.”

On Sunday morning, fans watching through the fence overlooking a pair of mounds at the Phillies’ complex were treated to the sight of Zack Wheeler and Aaron Nola pitching side-by-side.

Nola was throwing a side session in preparation for his second Grapefruit League start on Wednesday, before he joins Team Italy in the World Baseball Classic. And Wheeler was throwing just his second bullpen session after his thoracic outlet decompression surgery last September.

Wheeler, who had a blood clot near his right shoulder removed, threw 25 pitches on Sunday. He started mixing in his splitter, after only throwing fastballs in his first session.

“Split was really good,” Thomson said. “Had a lot of bottom to it. He threw the fastball where he wanted to.”

Wheeler is so far remaining on a typical build-up schedule, which involves two days off between bullpens. His next session is planned for Wednesday, and Thomson said he will start throwing other pitches in his arsenal and spinning the baseball more.