It didn’t take long for Luisangel Acuña to atone for his first MLB error. After the rookie shortstop’s missed catch at second base helped give the Nationals an early lead Tuesday, Acuña delivered an RBI double and his first MLB home run as the Mets won, 10-1, and increased their lead over the Braves in the NL Wild Card standings. “He’s calm. Poised,” Mets manager Carlos Mendoza said of Acuña. “It’s just, like, he belongs in the big leagues.” With the victory, the Mets (83-68) went up by two games over the Braves for a Wild Card spot with 11 games to play. Atlanta lost, 6-5, in Cincinnati on Tuesday night after leading 5-1. Making his first-ever start at Citi Field, the 22-year-old Acuña dropped a throw from third baseman Mark Vientos on a would-be force out in the top of the third inning. The ball scooted away from second base, allowing Washington’s Jacob Young to advance to third as CJ Abrams reached safely at first. James Wood’s force out then put Washington up, 1-0, on an unearned run for Mets starter Tylor Megill. But Acuña responded. In the bottom of the third, Acuña lined a run-scoring double against Nationals starter Mitchell Parker, tying the game, 1-1, with his first career RBI. Acuña came around to score the go-ahead run on a two-run bloop single by Pete Alonso, and Vientos capped a four-run inning with a sacrifice fly. Acuña added a sixth-inning single, then scored on Alonso’s three-run home run. The 375-foot blast was Alonso’s team-leading 33rd home run and gave him 86 RBI, tying him with shortstop Francisco Lindor for the most on the Mets. And in the bottom of the eighth, Acuña ripped a 414-foot solo shot against reliever Joe La Sorsa. He finished 3-for-4 with two RBI and three runs from the No. 9 spot in the lineup. After Tuesday’s powerful performance, Acuña said he received a message from his older brother, Braves superstar Ronald Acuña Jr., who helped him prepare for the majors. “That confidence comes from my brother,” Acuña said. “Sometimes I’ll ask him, ‘Hey, what’s that like in the big leagues.’ But it also comes from the practice. All the work that we put in, that’s where all of that confidence and comfort comes from.” Acuña said his sibling, who is out for the season with a torn ACL, intends to attend the Mets and Braves’ potentially pivotal three-game series next week in Atlanta, where the brothers plan to swap jerseys. Acuña repeatedly gave Mets fans reasons to cheer Tuesday, as did the Braves’ loss, which earned an eruption from the Citi Field crowd as that score became final. The Mets began Tuesday only a game behind the Diamondbacks for the second Wild Card position. Acquired in the July 2023 blockbuster trade that sent Max Scherzer to the Rangers, the speedy Acuña made his MLB debut Saturday in Philadelphia and has now appeared in four games. The rookie is part of the Mets’ solution at shortstop as Lindor recovers from a lower back injury. After an MRI came back clean Monday, Lindor said he plans to return this season, and possibly this week, but he missed his second game in a row Tuesday. Lindor has now either left early from or missed five games in a row. “It doesn’t come down to one individual,” Alonso said. “This is a group effort, and all of us have risen to the occasion. Obviously we miss him, because [Lindor is] just an unbelievable player on both sides of the ball, but all of us, it’s the task we have to deal with.” That Acuña is factoring into that effort shows how far he’s come since beginning the year with a .215 average through 31 games at Triple-A. “When players struggle in the minor leagues, you find out a lot about [them],” Mendoza said. “I’m gonna go back to the conversation that I was having throughout the year with Dickie Scott, our manager at Triple-A, and that was one of the things that he always said: ‘This guy’s going through it, but he posts. He wants to be in the lineup. He brings the energy every day.’” Also coming up big was the towering Megill, who struck out four against two hits and two walks over six solid innings Tuesday. Megill boasts a 1.69 ERA in four starts since being recalled from Triple-A Syracuse on Aug. 30 to replace the injured Paul Blackburn. The Mets won all four of those games. “He continues to give us a chance to win baseball games,” Mendoza said. “The sinker’s been a pitch for him that he knows he can throw at any time.” It’s been quite the turnaround for Megill, who owned a 5.17 ERA when the Mets optioned him to the minors in early August. That ERA is now down to 4.08. The Mets continue to handle their business against Washington (68-83), the final team with a losing record remaining on their schedule. The Mets are now 10-2 this season against the Nationals, whom they will attempt to sweep Wednesday night.