Luis Severino of the Yankees walks to the dugout against...

Luis Severino of the Yankees walks to the dugout against the Red Sox at Yankee Stadium on Aug. 12, 2017. Credit: Jim McIsaac

Big game, bad loss. And no excuses from the Yankees.

Their manager and players usually try to find something positive in any defeat, but no one resorted to that Saturday after a 10-5 loss to the AL East-leading Red Sox that dropped them 4 ½ games behind.

“When you’re playing the team that’s ahead of you, every game’s magnified a little bit,’’ Chase Headley said. “So certainly we need to try and go out and win the series [Sunday night]. It’s a big game for us.’’

A day that started ominously ended on the same note with questions about the rotation and the continued struggles of Aaron Judge.

Even before the game began, Masahiro Tanaka was placed on the disabled list with inflammation in his right shoulder, joining CC Sabathia on the sideline. Then Jordan Montgomery, Sunday night’s scheduled starter, had blood running from a cut on his right ear after being hit by a fly ball during Boston’s batting practice. He is expected to make the start.

The game, such as it was, offered no refuge. Luis Severino (9-5), the de facto ace of the staff, was charged with a career-high 10 runs in 4 1⁄3 innings. He was done in by two three-run home runs by Andrew Benintendi in the first five innings.

“He wasn’t executing his pitches today,’’ Joe Girardi said. “He made some mistakes with location, I think, with the fastball and some sliders. He’s been so good and executing so well. This shows that he’s human.’’

The Yankees needed better than human. “I think I’m trying to pitch too perfect,’’ Severino said.

He retired the first seven batters but issued consecutive one-out walks to Christian Vasquez and Jackie Bradley Jr. in the third. Eduardo Nuñez then sent a grounder to third that was fielded by Todd Frazier, but he dropped the ball on the transfer while trying to throw to second for what he hoped would be the beginning of a double play. Instead, the bases were loaded.

“I rushed, that’s basically it,’’ Frazier said. “I caught it but tried rushing the throw and couldn’t get a handle on the ball. Big play in the game. Big mistake, but you know, Sevy’s so good, I thought we were going to get out of it. But like I said, it was a big mistake, big part of the game. Something I take responsibility for.’’

Severino didn’t blame the error. “That’s part of the game. That can happen all the time,’’ he said. But Mookie Betts grounded a two-run single to left and Benintendi gave the Red Sox a 5-2 lead with his first three-run shot. His second made it 8-3 in the fifth.

The Yankees actually took a 2-0 lead with two outs in the first on Gary Sanchez’s 19th home run, a line drive inside the rightfield foul pole on an 0-and-2 pitch from lefthander Drew Pomeranz. Headley and Jacoby Ellsbury hit consecutive homers to lead off the ninth, but not much else occurred in between — aside from the Yankees’ inability to capitalize on a bases-loaded, none-out situation in the fourth. After Ellsbury’s RBI groundout, which brought the Yankees within 5-3, Ronald Torreyes and Brett Gardner popped up with runners on second and third.

Judge went 0-for-4 and twice was called out on strikes on sharp curveballs. He has struck out at least once in a club-record 29 straight games — Adam Dunn holds the major-league record with 32 — and has fanned 48 times in 100 at-bats in that span.

On June 12, Judge was a Triple Crown threat and had a .347 batting average. He’s down to .289.

Girardi had been reluctant to characterize Judge’s free-fall as a slump. Now he might look to rest Judge. “It’s something I can definitely think about it,’’ he said. “You know, we’re trying to get him back on track. It’s been a struggle, there’s no doubt about it the second half. It’s definitely something I’ll think about, sure.’’

Judge was not available after the game.

There’s also the issue of starters. Montgomery, who went through the concussion protocol, will be evaluated Sunday before being sent out against the Red Sox. No starter has been named for Monday night’s game against the Mets in the beginning of a four-game interleague series. Newcomers Sonny Gray and Jaime Garcia likely will pitch in the series.

“It’s not what you want this time of year,’’ Girardi said of the rotation. “We’ve had a couple of people get nicked up. Guys are going to have to step up. It’s probably a darn good thing that we made the additions that we made or we would be really, really short."

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