It’s nearly decision day for the Yankees when it comes to Anthony Volpe.

The shortstop was slated to play his final minor league rehab game Sunday with Double-A Somerset, as his 20-day window closed in his rehab assignment from offseason surgery to repair a torn labrum in his left shoulder.

But what once was considered almost a formality — that Volpe would reclaim his starting job at shortstop with the Yankees as soon as he was able — is now not so simple.

The Yankees have to decide by Tuesday’s game against Texas whether to activate Volpe or option him to the minors.

Prior to Sunday’s game against Baltimore in The Bronx, Aaron Boone said no decision had been made, in part because the Yankees have been playing as well as any team in the majors and José Caballero has been a significant part of that success.

“Caballero is playing the heck out the position and is playing really well,” Boone said. “That complicates it… José has played himself more playing time. I love the idea of Jose being in a super-utility role because he’s so good at it, but you also can’t ignore he’s played so well defensively at shortstop [and] been a real spark for us offensively.’’

Boone also noted they’d have to figure out the best role is for Volpe, who the manager said “is getting ready to play shortstop” and not preparing for a utility spot.

It’s a nice problem for the Yankees to have, since they entered Sunday having won 12 of their previous 14 games.

On April 10, shortly before Volpe’s rehab assignment began, general manager Brian Cashman said of Volpe returning to his everyday job, “That’s always been the plan. But ultimately, that’s that’ll be the manager’s call.”

Caballero has held up better than expected playing regularly at short and the Yankees have excelled with him there.

Caballero entered Sunday with a .935 OPS in his previous 19 games and added seven stolen bases — while also in the midst of a 17-game errorless streak.

In the minors, Volpe entered Sunday with just one extra-base hit in 45 plate appearances and the Yankees haven’t skipped a beat without the 25-year-old, who disappointed on both sides of the ball last year, while playing the injured shoulder.

“We’re off to a really good start,’’ Boone said of the team. “[Caballero] has been right in the middle of that defenivsely [and] offensively. So he’s earned some opportunities there. It’s really as simple as that [and] then weighing what’s the best thing for our team moving forward.”

And Boone also noted, “it’s a long season. We’re in this moment in time you get trapped in little bit, but there are gonna be so many opportunities for diff guys. The fact is, we’re probably as deep as we’ve ever been. We have real competition for real spots and real roles on the team that we haven’t had in some portions of seasons.”