Why the Phillies are encouraging Orion Kerkering to throw his two-seam fastball more often

Of the 60 big-league pitches Phillies reliever Orion Kerkering threw last season, 85% were sweepers. It’s hard to fault him for leaning on that pitch. It was difficult for hitters to pick up on, and even more difficult given how Kerkering was manipulating it — throwing it in different spots and with various speeds and movements.

But at the end of the day, it was still something hitters could expect to see. So, this offseason, Kerkering and the Phillies pitching coaches went back to the drawing board. They decided to add a two-seam fastball to his arsenal, to complement his four-seam fastball and his sweeper. The idea was to be less predictable.

Kerkering has done a better job of increasing his four-seam usage but has thrown only three two-seam fastballs this year. He used it quite a bit during his rehab outings at the beginning of the season but has had trouble finding the right spots to use it in games.

“When you’re at the big-league level, closer games, you don’t want to experiment,” he said. “So I think it’s learning to trust it. I’ve been throwing it a lot more in the bullpens and catch play and all of that stuff, so I think I keep building it up a little bit.”

Kerkering doesn’t go into each outing aiming to throw a certain amount of two-seam fastballs. Instead, the Phillies have encouraged him to map out certain situations, to be mindful of which hitters would struggle against the two-seamer and use it in those at-bats.

He has had a strong start to the season so far — posting a 1.17 ERA through seven outings going into Sunday night’s game against the Giants — but they think adding the two-seamer will accentuate the other pitches in his arsenal.

“By throwing a two-seam, he probably feels a difference in his four-seam,” said pitching coach Caleb Cotham. “So, on his four-seam, instead of laying down and running more than it carries, he can have an opportunity to feel a little bit more backspin, and a little more sink or run in the two-seam.

“I think [the sinker] also just makes his sweeper harder to sit on. Especially if he shows the ability to throw it for a strike. Not necessarily even command a specific spot, but make hitters account for a side of the plate.

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“Something we say is if you’re playing poker, you don’t want to play poker in a way that the opponent can go all-in on something you do. So, if you never do it, that’s easier to go all-in on the other thing. For him, it’s ‘Am I doing it enough to make the hitter think about it? And have to plan for it?’ That’s really it.”

Kerkering has found himself overthinking the pitch at times, along with where he’s locating it. Cotham has encouraged him to think less, and let the pitch move the way it naturally moves. He is 23 years old and in his first full big-league season. He has the stuff; now, he’s learning how to use it.

Giants right-hander Mason Black will make his major league debut Monday afternoon against the Phillies. Black is a Scranton native who grew up a Phillies fan and attended Lehigh University. … Phillies manager Rob Thomson said reliever Luis Ortiz, who was placed on the injured list on March 31 with a left ankle sprain, has been shut down for the time being. Said Thomson: “He’s basically got the same thing as [Yunior] Marte. He’s got inflammation in his shoulder right now. It’s still going to be a few days before he picks up a baseball. At least a few days.”