Drayer: Mariners’ Justus Sheffield may have just had fastball breakthrough

Mar 8, 2020, 5:44 PM

Mariners pitcher Justus Sheffield had success Sunday using a two-seam fastball. (Getty)

(Getty)

Mariners Insider, Seattle Sports

In a classic case of a spring training box score not always telling the full story, the Mariners may have seen a very significant development on the field for Justus Sheffield on Sunday in Scottsdale, Ariz.

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The line for Sheffield against the Giants was three innings pitched, allowing one run on one hit with no walks and five strikeouts, and that looks decent enough. But when you factor that he introduced a new pitch into the equation, abandoning his four-seam fastball and going exclusively to the two-seamer? Well, that made for one very good day for Mariners pitching coach Pete Woodworth.

“It was awesome,” Woodworth said on the field after the game. “He just trusted something that he can do naturally. Him and Murph (catcher Tom Murphy) had full conviction in it and that was the best fastball and best fastball command I have seen him have.”

Woodworth was the pitching coach at Double-A Arkansas last year when Sheffield was sent there after struggling mightily in Triple-A, so there is a good amount of familiarity. There is also a good measure of trust. Shortly after Mariners spring training began, Woodworth and Murphy began talking about the possibility of getting Sheffield to go to the two-seamer.

“It’s one of those things where you kind of want to feed the beast,” said Murphy. “If a four-seamer isn’t necessarily at the upper echelon, then why push something that is not going to be a great pitch when you can make it a two-seamer and now all of a sudden that low spin rate plays to his advantage. It was phenomenal today.”

The move was a case of working better with what he had. Sheffield’s four-seam fastball had the third lowest spin rate in baseball last year and was hardly a weapon for him. While he would get movement on it, the movement was unpredictable. That was not the case with the two-seamer, according to Murphy.

“At times his four-seamer did whatever it wanted to do,” said Murphy. “Today’s movement was the same every single time. It was really, really good.”

Sheffield has been working on the pitch in bullpens for the last couple of weeks but Sunday was the first time he threw it in a game. He was all in, pushing the four-seamer to the side 100 percent in favor of his new pitch. The reward, immediate.

“I really liked it,” said Sheffield. “It helped me stay closed in my mechanics, just mentally thinking I had to stay closed to get that pitch sinking and moving. I’m a pitcher that if I fly open it’s not a good day. It keeps me on track, keeps me going.”

Sheffield indicated that the four-seamer could be shelved for awhile but hopes it’s a pitch he can go back to in time. For now, with the two-seamer it appears there are much better answers to some of the struggles he has had.

“We just kind of saw with the four-seam, he’s been working on it awhile,” Woodworth pointed out. “That’s what he has always thrown. But his other pitches are off his two-seam grip so they were kind of contrasting ideas. The first day he put the two-seam in his hand he said ‘This feels great.'”

The slider has been Sheffield’s No. 1 pitch and will remain so for the foreseeable future. With the addition of the two-seamer, however, he now has better weapons to attack right-handers with a change-up and two-seamer that break away and a slider that comes in. An added bonus, he’s managed to take a little off the change-up, giving him more separation with the fastball. The change-up that was thrown around 89-90 mph last season has been more 84-85 mph, which will play much better off his 92-93 fastball.

It was just his first outing with the change but the reviews were stellar. For his part, Sheffield said it is too soon to get too into the movement of the pitch. For now he is working day to day with it as he learns just what it will be. What it was on Sunday left all involved very pleased with the fact that he decided to commit to it and take it into a game.

“Honestly from pitch 1 today – meaning his bullpen – it was the best I have ever caught from Justus Sheffield,” said Murphy. “It was the most natural I’ve seen his fastball move. His four-seamer had this very low spin to begin with. … Him switching to the two-seamer, I think is going to benefit him in the long run and you saw that today.”

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