McCutchen hit his second home run in two days, Betances pitched out of a bases-loaded jam in the ninth inning and New York held off the Seattle Mariners 4-2 on Saturday night.
Austin Romine hit a go-ahead homer in the seventh for the Yankees, who moved within 7 1/2 games of first-place Boston in the AL East with 20 to play. New York leads Oakland by 3 1/2 games for the league's top wild card.
"Tonight he finds himself in a little bit of trouble, but he keeps making pitches," Yankees manager Aaron Boone said. "He kept pounding the strike zone with his fastball and breaking balls, and he came up with a lot of big pitches in that inning. I was just proud of Dellin."
"Everyone knows Betances has great stuff," Mariners manager Scott Servais said. "We hoped to put a little pressure on him and we did. You have to try and look for a mistake. We got some traffic out there, but just didn't get the big hit at the end. It's frustrating. It's been a struggle for a while. You have to square a few more balls up."
With 20 games remaining, Seattle dropped 7 1/2 behind Oakland for the second AL wild card.
Yankees starter Lance Lynn (9-10) allowed three hits and two runs in six innings. He is 2-2 in eight starts with the team.
"My cutter was there tonight," Lynn said. "For the most part, the command was probably the best it's been all year. Most of it was just in my mind and telling myself not to do too much. Stay within yourself and do what you have to do to put it where you need to. And I was able to do that for the most part."
Mariners starter Felix Hernandez left in the fifth with right hamstring tightness.
"I slipped a little on the second batter, but I felt it in my last start," Hernandez said. "It was hard to push off."
McCutchen led off the game by sending Hernandez's changeup down the left-field line and into the seats for his second home run with the Yankees.
Mike Zunino tied it in the third with a homer to straightaway center, his 19th of the season.
Giancarlo Stanton gave New York a 2-1 lead in the fifth on a sacrifice fly to right. The inning started with back-to-back walks by Hernandez before he exited with the hamstring injury.
"Felix felt it more as the game went on," Servais said. "He gave us what he had tonight. We'll see how he feels going forward."
"It's fun to contribute," Romine said. "Every time you get in this game you want to help contribute for this team, whatever it is, however it is. We've got some boys who can put the ball in the seats. It's fun to be a part of it."
"Darryl and I were best friends," Servais said. "That night was really special to me. Games like that with people you're that close to, you never forget."
Servais remembers something he told Kile that night after the game.
"Darryl and I were very competitive back and forth. It was like, `Don't shake me off,' or `Yeah, OK.' Just a pitcher-catcher thing. And I made a comment that night that one day when we're 55 we'll argue about who was right. Unfortunately, I'll never get to do that with him.
"But I recently was able to spend time with his wife and their kids and see how they're coming along when we were in San Diego. It was good to see them."
Yankees: 3B Miguel Andujar left the game in the ninth inning when he was hit by a pitch on the right forearm. ... SS Didi Gregorius was back in the starting lineup, one day after coming off the 10-day DL. Gregorius, who missed 16 games with a bruised left heel, was 0 for 3 and played six innings before being replaced by Adeiny Hechavarria. Gregorius said Friday he is ready to go all out after playing the last four innings, but Boone wants to be cautious. "Any time you have a player of that caliber leave, it's hard to keep him out," Boone said. "We'll be excited to get him back, but we also want to be smart about how we bring him back and get him up to full speed."
Mariners: Cano exited in the ninth when he was hit by a pitch on the left foot. "He's hobbling around," Servais said. "Hopefully it's nothing serious and it's just a bruise."
Yankees lefty CC Sabathia (7-6, 3.54 ERA) makes his 26th start of the season Sunday. Sabathia's 2,970 career strikeouts are the most among active pitchers. He is 17th all-time and third among lefties. RHP Erasmo Ramirez (2-3, 5.56) gets his seventh start of the season for the Mariners and fifth since coming off the disabled list Aug. 12. Ramirez has allowed one earned run or less in four of his last five starts.
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