NEW YORK -- The Yankees’ offense has been waiting several days to breathe a sigh of relief, anxiously seeking that one big hit that would open the floodgates.

They finally got it Wednesday night, allowing the 42,512 fans in the ballpark -- at least those who waited out an hour of heavy rain in the seventh inning -- to let out some of their own emotions.

After Aroldis Chapman served up a three-run double by Francisco Mejía in the top of the 10th, the Yankees answered right back, loading the bases for Josh Donaldson, who drilled a walk-off grand slam against Jalen Beeks for a much-needed 8-7 victory.

“There's not too many better feelings in the world than hitting a walk-off homer,” Donaldson said. “As a kid, that's what we all put ourselves in those moments for. It was thrilling; I look forward to carrying some of this momentum going forward.”

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Donaldson knew it was gone the moment he hit it, flipping his bat as he watched the ball disappear into the seats beyond the right-field wall. The Bronx crowd -- which had been jeering the home team just minutes earlier -- launched into a frenzy that had yet to be seen during the home stand.

“That's a pretty good release of some joy coming out of that dugout, just with how it's gone here lately,” manager Aaron Boone said. “For being the regular season and being in August, that was a special one.”

The win snapped the Yankees’ three-game losing streak, pushing their lead in the American League East back to 10 games over the Rays and Blue Jays.

It wasn’t shaping up as a good night for the Yankees, who had clawed back from a 4-0 deficit in the sixth, tying the game on Anthony Rizzo’s leadoff homer in the eighth.

Once the game moved to extra innings, things unraveled in the 10th for Chapman, who walked two batters before giving up Mejia’s three-run double. The Yankees, losers of 11 of their last 13 entering the game, appeared headed for their first three-game series sweep at home and their smallest division lead in more than two months.

“It's kind of that gut punch right there,” Boone said. “But credit to the guys; it was like, ‘Hey, let’s keep fighting.’”

Aaron Judge began the inning on second base, then Gleyber Torres -- who started the Yankees’ comeback with a two-run homer in the sixth -- singled to right field, putting runners at the corners. Rizzo worked a four-pitch walk, bringing Donaldson to the plate.

Mired in a 3-for-28 slump with no extra-base hits during that stretch, Donaldson thought back to his at-bat against Beeks on Monday, when the left-hander struck him out on three filthy changeups. Beeks threw a fastball with his first pitch this time, so while Donaldson was still prepared for a changeup, he was ready for another heater.

When it came, he didn’t miss.

“I think that's who we are as a team; I don't think the last two weeks is who we are,” Donaldson said. “I think that's more of a blip than anything. For us to be ourselves, go out there and compete to the last final out and pick each other up, that's what we do.”

Donaldson -- who joined Babe Ruth (1925) and Jason Giambi (2002) as the only Yankees in history to hit a walk-off grand slam with his team trailing by three runs -- was mobbed by his teammates after he rounded the bases, the entire team celebrating a victory that seemed unlikely minutes earlier.

“The guys were pumped,” Donaldson said. “How the game progressed and kind of how the back-and-forth battle happened there and we were able to come back there with our backs against the wall, I definitely think that was probably a release of some joy and some frustration over the past couple weeks.”

For the Yankees, it was their 13th walk-off win of the season, but given their recent slide and offensive woes, Donaldson’s blast could be remembered as one of the most important hits of the year.

“We know we're a really good team,” Boone said. “We’re struggling, obviously, right now and going through it, but at the core, it's a confident group and we know we have to keep our head down, focus, grind through this. That was a special one that hopefully, we can look back on fondly."