MILWAUKEE — Pete Alonso hit a go-ahead, three-run homer off All-Star closer Devin Williams in the ninth inning and the New York Mets beat the Milwaukee Brewers 4-2 on Thursday night to win their NL Wild Card Series. With their latest thrilling comeback in the decisive Game 3 against Milwaukee, the Mets advanced in the playoffs for the first time since winning the 2015 National League pennant. They moved on to a best-of-five Division Series beginning Saturday in Philadelphia against the NL East champion Phillies. It will be the first postseason meeting between the heated rivals. “This has been unreal. What a ride,” Alonso said. “I’m just excited to help keep this team alive.” The slugger became the first major leaguer to hit a go-ahead homer when his team was trailing in the ninth inning or later of a winner-take-all postseason game, according to OptaSTATS. “This is something that you practice as a kid in the backyard,” Alonso said. The NL Central champion Brewers, making their sixth playoff appearance in seven years, still haven’t won a postseason series since reaching Game 7 of the 2018 National League Championship Series. This loss will be particularly painful. “I love this team,” manager Pat Murphy said. “I love them. I’ll never be able to duplicate 2024. It didn’t end the way we wanted to. It ended tragically, actually.” Milwaukee appeared to have the victory in hand after pinch-hitter Jake Bauers and Sal Frelick broke a scoreless tie by opening the seventh inning with back-to-back homers on consecutive pitches from Jose Buttó. Rookie right-hander Tobias Myers and three Brewers relievers combined on a two-hit shutout through the first eight innings. In fact, 12 straight Mets had been retired when they entered the ninth against Williams, a two-time NL reliever of the year who had earned the save Wednesday in Milwaukee’s Game 2 victory. But he wasn’t his normal self on this night. “I’m not going to make any excuse,” Williams said. “I didn’t execute the way I needed to. They got the job done and I didn’t.” Francisco Lindor opened the inning by working an eight-pitch walk. Mark Vientos struck out, then Brandon Nimmo singled sharply on an 0-2 pitch to put runners at the corners. That brought up Alonso, who has 226 career home runs in six seasons but hadn’t delivered an extra-base hit since homering on Sept. 19. “I know Devin has great stuff,” Alonso said. “I’ve seen him pitch a ton. We were teammates in the WBC (World Baseball Classic). He’s a tough AB.” After getting ahead 3-1 in the count, Alonso drove an 86 mph changeup to the opposite field over the wall in right. He put his fingers to his mouth in a “chef’s kiss” gesture as he rounded first base and gave New York the lead. Alonso can become a prized free agent after the World Series, so it could have been his final plate appearance with the only professional franchise he’s played for if the Mets had fallen short. Instead, he sent them on to the next round with the biggest home run of his career. “Pete Alonso was one swing away from people going crazy about him. And that’s what happened,” Lindor said. Williams remained in the game but never regained his footing. Jesse Winker was hit by a pitch with two outs, stole second and scored an insurance run on Starling Marte’s single to right. Winker, a former Brewer who was showered with boos throughout the series, screamed and slammed his helmet to the ground after sliding across the plate. The ninth-inning rally continued New York’s storybook season. The Mets were 22-33 in late May but had the best record in baseball the rest of the regular season. They didn’t earn a playoff berth until scoring all their runs in the final two innings of an 8-7 comeback victory at rival Atlanta in the opening game of a makeup doubleheader Monday, the day after the regular season was supposed to end. New York is the first team to clinch a postseason spot and a playoff series by winning both games after trailing in the ninth inning or later. “With what’s transpired this season, it seems only fitting,” Nimmo said. “We seemed down and out. At the beginning of the season, we were written off. Obviously it was compounded in April and May. Then we went on this just unbelievable run of being the best (team) in baseball for the next four months, having the team meeting, pulling ourselves up. “And that’s kind of how this game was. This game, we were down and out for eight innings, and we just said, ‘You know what? We’re just going to keep shooting our shots until the end, and we’re going to see what happens.’” Frelick led off the bottom of the ninth with a single, but Joey Ortiz struck out and Brice Turang hit into a double play to end the series. “It sucks, plain and simple,” said Frelick, whose homer was his first since mid-May. “We got beat and it’s going to be something I think we all can remember as a group, though, going into next year.” Edwin Díaz pitched 1 2/3 innings of scoreless relief to earn the win. David Peterson, making his first relief appearance this season, worked the ninth for his first major league save. The game started out as a pitchers’ duel between Myers and New York left-hander Jose Quintana. Myers pitched five shutout innings, while Quintana held the Brewers scoreless through six. UP NEXT New York went 6-7 against the Phillies during the regular season and finished six games behind them in the division standings.