SCOTTSDALE, Ariz. -- Justus Sheffield had to wait longer than expected to make his Mariners’ debut, but the club’s new top pitching prospect lived up to expectations when finally given the chance with a strong two-inning outing in Sunday’s 4-2 victory over the Rockies at Salt River Fields.

Sheffield, acquired from the Yankees in the James Paxton trade, had been penciled in for his first appearance on Thursday, but rain wiped out that opportunity and he wound up being pushed back a few days by a slight blister issue on his pitching hand. But the 22-year-old left-hander blistered the Rockies once he got rolling, striking out four in two hitless innings in relief of starter Wade LeBlanc.

Other than a leadoff walk in his first frame, Sheffield was spotless, even overcoming a catcher’s interference call on Jose Lobaton that nullified a popout to the third batter he faced and put him in an early pickle with runners at first and third and one out.

The youngster struck out Ian Desmond and Chris Iannetta to end that threat, then zipped through a 1-2-3 inning with two more strikeouts to put a nice bow on his debut.

“Justus threw the ball really well,” manager Scott Servais said. “The leadoff walk, but he settled in. Very aggressive. I really like how his stuff works. He threw some good changeups and his go-to pitch, his out pitch, has always been his slider. Really good start for him. There’s a lot of upside. I’m excited to see that.”

Sheffield worked this winter on refining his changeup, which, along with his 93-94 mph fastball and quality slider, makes him a potent force.

“I feel I’m in a good spot right now,” Sheffield said. “There’s room for improvement with my slider, changeup, fastball. But right now I feel I’m in a good spot. It’s just getting out there and getting the repetitions.”

Whether Sheffield can break camp with the Mariners remains to be seen, as the initial plan is to start him out with Triple-A Tacoma, unless something happens with the current five-man rotation. But he’s clearly knocking on the door and it’s only a matter of time before he gets that shot.

“Justus carries himself so well,” Servais said. “Just the confidence level. He knows this is his time. He’s done what he needs to do at the Minor League level. He still has some things to work on, but he wants to make a good first impression and he was very good today.”

Shed continues to shine

Second base prospect Shed Long has been the Mariners’ best hitter in the first week, and he added an RBI single on Sunday to the long home run he took off the batter’s eye in center field in Saturday’s 6-4 loss to the Padres.

The 23-year-old played left field for the first time in the final four innings Sunday as the Mariners continue looking for ways to use him.

“My eyes are wide open on Shed Long,” Servais said. “I think the key is we need to give him as much versatility as possible to get that bat in the lineup. It is really a quick bat. He knows the strike zone very well. We saw him in left field today, he’ll play third base [on Monday]. Second base is his natural position. It’s just an electric body. He likes to get out here and have fun. He has some swag to his game and is a fun guy to watch.”

Plan B in center field

With Mallex Smith still a week or more away from even beginning to swing a bat as he lets his strained right elbow heal, the Mariners will almost certainly need a solution in center field for the two-game Opening Series against the A’s in Tokyo to open the regular season.

The likely first option will be to slide right fielder Mitch Haniger over to center field, since the Mariners have other options in the corner spots, particularly with Ichiro Suzuki expected to be on the 28-man roster that will be allowed for the two international games.

Domingo Santana and Jay Bruce can both play the corners, as could whoever makes the club as the utility player, which appears to be a battle between Dylan Moore and Kristopher Negron. Long now could be emerging as a corner outfield option as well.

The Mariners prefer Haniger in right field, but he started 26 games in center last year and will work some there this spring as well.

“We’ll give him some center field time when we get closer to breaking camp here,” Servais said. “Certainly we want him to be comfortable out there. The big thing right now is just get some at-bats, get your legs under you. He’ll be fine in center field. I’ve talked to him already about it. He kind of knows the plan.”

Up next

Japanese standout Yusei Kikuchi will make his MLB debut Monday against the Reds at Peoria Stadium. Shawn Armstrong and Dan Altavilla are among the relievers slated for the 12:10 p.m. PT game, which will be televised live.