Lefthander Justus Sheffield impressed the Mariners in his first big league camp for the organization, specifically while focusing on developing his changeup and slider.
“We’re working on a few things,” Mariners manager Scott Servais told reporters. “But all three pitches (including his fastball) are working.
“I really like where he’s at. His slider is certainly an out pitch. It would be nice for him to throw a few more strikes, and I know he likes to take it down and in to the right. He can put them away with that pitch—but you also have to throw it for a strike.”
The Mariners coveted the 22-year-old Sheffield for his stuff. They traded ace lefty James Paxton to the Yankees for Sheffield and righthander Erik Swanson and outfielder Dom Thompson-Williams. But their emphasis has been on getting Sheffield to trust his repertoire.
“In the past I’ve been known to try and make a perfect pitch,” Sheffield said. “And then I fall behind in the count. I’m just looking at every count as 0-0 and stay ahead and try to attack and put them away.
“Just continue to attack—that’s kind of been the motto over here.”
Sheffield, an Indians first-round pick out of Tullahoma (Tenn.) High in 2014 who was traded to the Yankees in 2016, said it’s been an adjustment transitioning to the Marines’ camp this spring.
“I’m getting on a steady routine here, but it was a little different over there with the Yankees,” Sheffield said. “So it took a little getting used to kind of adjusting to the days we lift and things like that. I’m still getting my work in, it’s just about figuring out what days work best and how we go about bullpens and those things.”
It’s still more likely Sheffield opens the season at Triple-A Tacoma. Not only do the Mariners project to have a full rotation, but they would prefer to bring Sheffield up only when he’s most likely to stay up for good. Until then they want him to let it loose.
“Absolutely,” Servais said. “It’s like a number of our young guys. They have good stuff. Let it go. You don’t have to be perfect with the command all the time but trust your stuff.”