BOSTON -- After a week of subpar starts, it was imperative that Domingo Germán provide the Yankees with something resembling a deep outing. Austin Romine identified the poise in his pitcher's body language before a single strike crossed home plate, saying that the right-hander "was on a mission."

Mission accomplished. German struck out nine and pitched into the sixth inning while Romine and Didi Gregorius slugged homers off Chris Sale, helping New York salvage the finale of a four-game series at Fenway Park with a 9-6 victory over the Red Sox on Sunday night.

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"I felt it was my responsibility to go out there and put a stop to it," German said through a translator. "It's been a rough patch for us starters. Tonight I felt I needed to go out there and be aggressive."

Yankees starters had failed to complete five innings in seven straight games, a string that German snapped by limiting Boston to three runs and four hits over 5 1/3 innings. The win restored New York's lead in the American League East to nine games over Boston and 8 1/2 games over the second-place Rays.

"This was a bad week, but for Domingo to go out and do it, I'm not surprised," Yankees manager Aaron Boone said. "That moment for him wasn't too big. I knew he'd be in command of his emotions regardless of the outcome. He certainly was."

German notched his 13th victory, good for a share of the AL lead, as he held Boston hitless through the first 11 batters of the contest. Andrew Benintendi slugged a two-run homer in the fourth, halving the Yanks' lead at the time to 4-2, but the Yanks padded German's lead with a pair of sixth-inning runs.

A leadoff walk (German's only free pass of the night), Xander Bogaerts' double and a J.D. Martinez RBI groundout brought Boston within three runs, but Boone called upon Tommy Kahnle for the final two outs of that frame, freezing German's line. German threw 57 of 77 pitches for strikes.

"We needed that start from Domingo, badly," Romine said. "I think he came out and was the most calm I have seen him, the most collected I have seen him. I think he was on a mission and throwing some really good pitches there, keeping them off balance. It's the first time we’ve seen some off-balance swings. It was much needed and great."

Goin' deep

Leads have been difficult to come by in a series in which the Yankees were outscored, 44 to 22, but Romine put New York on top by reaching the Green Monster seats for a two-run shot in the third inning. Romine's third homer of the season came off the bat at 111.4 mph and traveled a projected 446 feet, according to Statcast.

"I was just trying to get something up," Romine said. "I've faced him a couple times before. They know I am looking first-pitch fastball, so maybe something up and in the zone [that I can] get a good swing off. I did."

Gregorius visited the right-field seats with a two-run homer off Sale in the fourth inning, and one night after posting the first four-hit game of his career, Urshela continued to swing a hot bat by adding a run-scoring double in the sixth off Sale. Urshela owns eight extra-base hits in his last six games.

"The power continues to play; I think everyone keeps waiting for [Urshela] to fall off," Boone said. "It's just more good at-bats and it seems like the better the competition, the bigger the spot, he seems to be a little better too."

Cameron Maybin also drove in a run off Sale, who was charged with six runs over 5 1/3 innings. Sale fell to 0-3 with a 7.71 ERA in three starts against the Yankees this year, having allowed 14 earned runs in 16 1/3 innings.

'Pen pals

New York owned an 8-3 lead after the top of the seventh, thanks to a bizarre error by center fielder Jackie Bradley Jr., who threw toward first base on a Gregorius flyout, believing that he had Luke Voit doubled off. No fielder was nearby to accept the throw as two runs came home.

Kahnle, Adam Ottavino, Zack Britton and Aroldis Chapman combined to close out the victory, though it wasn't exactly comfortable. Britton escaped a bases-loaded, one-out jam in the eighth, striking out Bradley and inducing Christian Vazquez to hit into a fielder's choice.

Benintendi stroked a two-run single off Chapman in the ninth, but the closer recovered to strike out Michael Chavis and seal New York's third win of their week-long trip to Minneapolis and Boston.

"This was heavy, this game," Boone said. "It looked like we were pulling away and going to walk away; they kept throwing baserunners up there to make it tough. Britt made some big pitches there to get out of the eighth and then Chappy the same."