NEW YORK -- They knew they’d need to punch back. A lot.

In this ballpark and against this opponent, the Mariners entered Tuesday at Yankee Stadium recognizing that they’d need to score early and often to have a fighting chance against the American League juggernaut, then hold them off when inevitable jams mounted.

Such was the precise case in a tense 8-6 victory over the team with the most wins in MLB. Seattle built an early lead, later extended it, watched it evaporate, then rallied to go back in front in a way that seemed both improbable yet vital on this grueling road trip.

Sam Haggerty was at the center of some late offensive heroics, leading off the seventh with a go-ahead homer and then scoring a critical insurance run with an excellent read and instincts on the basepaths. Then Andrés Muñoz put a bow on the utility man’s effort by working into and out of a bases-loaded jam in the ninth that saw the potential winning run on first and the 38,735 in the Bronx roaring.

It was the closest to a road postseason atmosphere that the ambitious Mariners have played in all year. Couple that with the anxiety of the Trade Deadline earlier in the day, and heart rates were high from when the first team bus arrived to when the last one left.

“Our guys believe in themselves,” Mariners manager Scott Servais said. “I said that earlier today, with the Trade Deadline and what we need to add to our team. Our team, we like our team. I love our team. Our guys like each other and they’re playing for each other.”

On a Deadline day that saw Seattle opt to add depth pieces but not an impact bat, Tuesday’s victory saw most everyone chip in -- even with Julio Rodríguez and Ty France recovering from wrist injuries.

Some examples:

• Muñoz, on four days’ rest, got two quick outs in the ninth but then surrendered a first-pitch single to DJ LeMahieu, a five-pitch walk to Aaron Judge and a four-pitch walk to Anthony Rizzo, setting up what seemed like a sure walk-off. Yet after a confidence-boosting mound meeting with teammates, he struck out Gleyber Torres to end the game. It was the opposite result of a May 22 loss in Boston, when he gave up a walk-off grand slam.

“Just a lot of support from them,” Muñoz said through interpreter Freddy Llanos. “They kept telling me how good I was, how good my pitches were and just to attack the guys, and it’s something that surprised me, the amount of support I received.”

• Three days after a self-inflicted wound that required stitches, Haggerty came up with the Mariners’ first pinch-hit homer against the Yanks since Jay Buhner in the 2001 AL Championship Series, taking over for Jarred Kelenic.

• Adam Frazier lined an RBI single just past the outstretched glove of LeMahieu that brought in Haggerty with the critical insurance run in the ninth. Frazier went 2-for-3 with two walks. He’s hitting .349/.389/.398 (.787 OPS) the past calendar month and becoming the consistent contributor the Mariners envisioned. Second base looked like a serious Deadline need one month ago, but Frazier’s emergence changed that.

• Cal Raleigh swatted his 15th homer in the second, then he helped navigate Muñoz through the jam in the ninth. Raleigh has some backup on the way when Deadline acquisition Curt Casali eventually arrives.

• Eugenio Suárez hit a Statcast-projected 432-foot, two-run homer in the first inning that gave Logan Gilbert an early edge. Suárez’s 17th homer was a microcosm of his streaky season, having slashed .167/.303/.204 (.507 OPS) since his most recent deep fly on July 13. But when he hits them, he does so in bunches.

• Carlos Santana, just after the Yanks pulled to within one, hit a two-run double in the fifth that gave Seattle more breathing room. He also had a sacrifice fly in the third. Santana is hitting just .183/.297/.376 (.673 OPS) since being acquired on June 27, but he’s had shining contributions in key moments, such as Tuesday.

“I think it's huge, for maturity and big moments and maturity against great teams like the Yankees,” Haggerty said. “For us to come back, for us to battle and end up getting a win, this is really big for our overall team and a lot of young guys in here to learn how to win.”

This seven-game weave through Houston and New York was always going to be the season’s most challenging. And though the Mariners have taken just two of six so far, the opportunity for a road series win against the AL’s best team is notable. Even in the highs and lows of this trip, they’re getting a taste of October -- and on Tuesday, they punched back big.