It’s not Daniel Murphy or Carlos Gonzalez. It’s not Eric Hosmer or Robinson Cano.

One young left-handed batter hits southpaws better than anyone else, and he’s a Yankee.

Didi Gregorius is that player.

The slick, 26-year-old shortstop improved his MLB-best average against left-handers on Sunday night, going 2-for-3 with a run scored against David Price to raise that average to .370 (30-for-81), and help the Yankees avoid a sweep in a 3-1 victory over the rival Red Sox at the Stadium.

While Gregorius has just one of his 11 home runs against lefties, his other numbers are impressive. He has a .847 OPS, and is slugging .449.

“I’m just trying to see the ball, try to get [my foot] down early, try to not to chase outside the zone. That’s what I’m trying to do,” Gregorius said. “Especially when I’ve got all the veteran guys here, we talk all the time about hitting.”

Of course, he’s having a breakthrough year against all pitchers, now batting a shade under .300 at .299 with a .791 OPS and 30 extra-base hits, just five shy of his career-high set last year. He singled to center field in the Yankees four-run third inning and doubled against Price down the right-field line in the fifth, ripping the ball each time.

After a strong first half, he’s picked up right where he left off, hitting safely in the last two games, and is batting .326 in 13 games this month after hitting a scorching .337 in June.

It was apropos, after all, that Gregorius was in the middle of the fourth-inning rally. He was followed by a Starlin Castro run-scoring double. Austin Romine plated Castro with a two-out single, giving the Yankees the lead for good, and Jacoby Ellsbury’s single drove home Romine. In all, the Yankees scored three runs on five hits, producing the kind of rally that was absent the first two forgettable days of the series.

“We just got some pitches up in the zone. Honestly, I couldn’t tell you if it was a fastball or changeup to [to me], I just knew it was up,” Romine said of his RBI single. “Any time you get a pitch up, especially with how good a pitcher he is, you have to take advantage of it. We put some good swings on the ball. It just fell for us tonight. It’s nice when it falls for you.”

It all started with Gregorius, which was symbolic because he’s represented a lot of the positive high points in what has been a mediocre season so far in The Bronx.