BOSTON — The Yankees have stayed atop the AL East even in Aaron Judge’s absence for numerous reasons, but playing clean baseball could be at the top of the list. 

With less margin for error, there’s less room for defensive mistakes. 

So the season-high four errors they made in Thursday’s 6-3 loss to the Red Sox at Fenway Park were especially tough. 

And even as they made the most errors in a game since the four they committed in a loss to Boston at Yankee Stadium last Aug. 21, there were even more miscues than the ones that made the stat sheet. 

“We just didn’t do a good job taking care of the ball,’’ Aaron Boone said. “It’s not up to where we’ve been playing or capable of playing. Ultimately, it was too much to overcome.” 

Among the culprits was José Caballero, whose defensive versatility is part of what the Yankees were looking for when they acquired him from Tampa Bay last season. 

But they probably didn’t foresee him starting in left field five times over an eight-game period as he’s been forced to with Judge and Trent Grisham sidelined. 

Caballero avoided making an error and made a nice running catch on Wilyer Abreu’s fly ball to deep left to open the bottom of the seventh, but his errant throw on Jarren Duran’s very shallow fly ball two innings earlier allowed Ceddanne Rafaela to score and helped Boston take control of the game. 

The fact that Rafaela even tried to score on the play indicated what the Red Sox thought of Caballero in left. 

“I try to help the team as much as I can,” said Caballero, who has started eight games in left in his career. “We have a lot of needs in the outfield right now.” 

Asked if he was surprised Rafaela was sent, Caballero said he anticipated it. 

“They’ve been challenging me a lot,” Caballero said of opposing teams looking to take advantage of his lack of experience at the position. “They know I’m new in the outfield. I expected him to go, and he did.” 

As for his throw home, which took Austin Wells away from the plate, Caballero said, “I put good velo on it. It was just a little off the line. And mistakes happen.” 

Before the game, Boone said he considered Jasson Domínguez in left and acknowledged Cody Bellinger as their best left fielder, but the Yankees went with Caballero in front of the Green Monster and Amed Rosario at third base. 

Rosario let Willson Contreras’ rocket 112 mph grounder go through his legs for a two-base error in the fifth, which allowed the first of four unearned runs to score against Cam Schlittler. 

This is the predicament the Yankees find themselves in with Judge and Grisham on the injured list. 

The issues weren’t limited to the outfield, as Wells was charged with an error on a catcher’s interference that wiped away a groundout by Abreu in the first. 

Schlittler threw a pickoff attempt at second base that went into center field for an error, and the right-hander also watched Caleb Durbin’s pop-up drop in front of him for an infield single in the second. 

Yerry De los Santos made the fourth error of the night in the eighth.