The Yankees' Tyler Austin, center, rushes Red Sox relief pitcher...

The Yankees' Tyler Austin, center, rushes Red Sox relief pitcher Joe Kelly, right, after being hit by a pitch during the seventh inning at Fenway Park on Wednesday. At left holding back Austin is Red Sox catcher Christian Vazquez. Credit: AP / Charles Krupa

BOSTON — Gary Sanchez broke out in a big way Wednesday night.

So did the bad blood that in many respects had been dormant in the Yankees-Red Sox rivalry in recent years.

And an unlikely Yankee, 26-year-old first baseman Tyler Austin, was at the center of it.

Sanchez homered in his first and third at-bats, which sandwiched a double in his second, helping to lead the Yankees to a 10-7 victory over the Red Sox in front of 32,400 fans on another 40-degree night at Fenway Park.

But pretty much all of the game specifics, including Masahiro Tanaka nearly blowing an 8-1 fifth-inning lead and Boston starter David Price leaving after one inning because of a possible injury, was overshadowed by the events in the top of the seventh.

With the Yankees leading 10-6, one out and the hard-throwing Joe Kelly on the mound, Austin stepped to the plate.

Austin helped clear the benches in the third when he slid a bit late into second and clipped the right ankle of shortstop Brock Holt with his left leg. Holt objected, words were exchanged — though nothing terribly heated — and the benches emptied, but that was about it.

“It wasn’t a dirty play,” said Giancarlo Stanton, who had three hits, including a two-run triple in the first. “You don’t need to drill him for that.”

Kelly felt otherwise, planting — though he somewhat laughably contended afterward unintentionally — a 2-and-1, 98-mph fastball into Austin’s left elbow area in the seventh, a pitch Aaron Boone called “unwarranted” and general manager Brian Cashman called “an overreaction on their part.”

Austin slammed his bat to the ground and charged Kelly, who got a couple of punches in at Austin before Aaron Judge plucked the pitcher off. The 6-7 Judge and 6-6 Stanton were among the first out and ended up holding back Kelly in the melee.

“Just protecting my guys,” Stanton said.

Said Judge: “How angry did it make us? No one ever likes getting hit with 98 to the back so everybody was pretty upset about it.”

Kelly and Austin, who appeared to land a punch to the face of Boston third-base coach Carlos Febles, and Yankees third-base coach Phil Nevin were ejected, as was reliever Tommy Kahnle. Boone said one of the umpires aggressively pulled Kahnle away during the fracas and the righthander’s reaction got him tossed.

“I’m just trying to defend myself,” said Austin, likely facing a suspension, as are several others. “I felt like it was intentional and I didn’t want to let anybody push myself around or do anything like that. Once I got hit it was going to happen.”

Of the slide, Austin said: “I wasn’t trying to hurt anybody, I wasn’t trying to take him out.”

No one in the Yankees clubhouse had an issue with Austin going to the mound.

“I don’t blame him at all,” said Nevin, a big-leaguer from 1995-2006. “I would have done the same thing. In no way was that a dirty slide.”

The game?

It was a nice bounce-back for Sanchez, who entered the night in a 1-for-33 skid, and for the Yankees (6-6). The night before the Yankees took it on the chin, 14-1, to fall below .500 for the first time this season.

The Red Sox (9-2), who took Price out after the four-run first inning for precautionary reasons because he was “experiencing a sensation in his left hand,” saw their nine-game win streak end.

“With two competitive teams, stuff happens,” Cashman said. “But there’s no reason for fisticuffs to happen because of that slide at second base.”

Will the bad blood carry over to Thursday’s series finale?

“I think it’s probably over with,” Boone said. “I think it’s over with. We’re just happy to come out of here with a win.”

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