Who’s the lesser-known Yankees prospect making run at playoff spot?

Yankees lefty prospect Stephen Tarpley appears to have a good chance at making the playoff roster, thanks to his ability to dominate left-handed hitters.

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BOSTON — In a Yankees clubhouse with top pitching prospect Justus Sheffield, it’s anther lefty rookie who’s building a strong case for a job on the postseason roster.

Stephen Tarpley got out the two left-handed Red Sox hitters he faced in a 8-5 win over the Red Sox at Fenway Park on Saturday.

The Yankees could be priming him for a lefty specialist job in October.

Manager Aaron Boone didn’t rule it out following the victory.

“After that first rough outing,” Boone said, “he’s come in and filled up the strike zone, and you get that sense that lefties don’t see the ball great against him. Even (Saturday), when he got into some deep counts, he didn’t budge. He kept pounding the strike zone and got two more big outs and continues to impress us and get our attention.”

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Tarpley has retired 12 of the 14 lefty batters he’s faced since getting called up to the majors.

In his last seven games, he’s given up no runs and just three hits and two walks while striking out seven over 5 2/3 innings. He was rocked in his first outing, giving up three runs in an inning.

Tarpley doesn’t appear on the Yankees’ top 30 prospects list on MLB.com. Meanwhile, Sheffield is the top guy there.

Boone was asked if using Tarpley against the Red Sox’s lefty hitters was an audition for how they could use him in the American League Division Series — if the Yankees make it that far. (They will have to beat the A’s in the AL Wild Card on Wednesday first.)

“We thought it would be a good spot to get Tarpley in and give him another run against a couple lefties. So, yeah, we kinda planned that out that way, Boone said.