NEW YORK -- With the Mets trailing by a run in the eighth inning, Pete Alonso drove a fastball from Tanner Rainey down the left-field line, well over the foul pole.
"I talked to it," Alonso said. "I was like 'stay fair, please' and it listened."
Alonso set the Mets rookie record for home runs before the All-Star break with 1½ months to spare, Amed Rosario had a winning infield single with two outs in the ninth and New York rallied from deficits three times to beat the Washington Nationals 6-5 Tuesday night.
Washington led 1-0 in the fifth, 3-1 in the seventh and 5-4 in the eighth, but the Mets (22-25) kept bouncing back and won their second straight game after general manager Brodie Van Wagenen said Mickey Callaway will remain the team's manager "for the foreseeable future."
Alonso's 16th homer broke the team rookie record for the first half set by Ron Swoboda in 1965. Alonso turned on a 1-2 pitch from Rainey (0-1), and the ball rose 126 feet and bounced off the Porsche Grille restaurant. The home run call on the field was upheld by a video review.
Rainey walked Adeiny Hechavarria and J.D. Davis with one out in the ninth, Kyle Barraclough relieved and Jeff McNeil grounded into a forceout that left runners at the corners. McNeil advanced on defensive indifference and, with Robinson Canó on deck, Rosario hit a two-hopper grounder to shortstop and beat Trea Turner's throw.
"He just willed himself to run faster it looked like to me," Callaway said "It was unbelievable."
Rosario made it to first in 4.03 seconds according to StatCast.
"I felt like I threw it good, but he can run," Turner said.
Rosario clapped his hands and was mobbed by teammates between second and third before getting doused by Alonso.
"The moment I hit that ball, I immediately thought I have to get there," Rosario said through a translator.
Edwin Díaz (1-2) worked around a ninth-inning single for his first win with the Mets. Washington (19-29) lost its third straight and dropped a season-high 10 games under .500
Mets starter Zack Wheeler gave up three runs and four hits in seven innings, while Washington's Erick Fedde allowed one run and four hits in five innings.
Juan Soto homered in the second, but McNeil tied the score with a fifth-inning single. Brian Dozier put the Nationals back ahead with a two-run homer in the seventh, but Davis's three-run pinch homer off Wander Suero gave the Mets a 4-3 lead in the bottom half.
Turner hit a tying double in the eighth off Jeurys Familia and scored on Soto's double against Daniel Zamora.
"We're right there, but we've got to win," Washington manager Dave Martinez said. "The bottom line is we have to start winning."
Nationals: RHP Jeremy Hellickson (strained right shoulder) was placed on the 10-day IL. Washington manager Dave Martinez does not think it will be a long stint. Hellickson saw a doctor Monday and was cleared to keep throwing. ... RHP Aníbal Sánchez (strained left hamstring) had a bullpen session Tuesday and could throw a simulated game Friday.
Mets: OF Michael Conforto (concussion) rode a bike on Monday, his first physical activity since being placed on the 7-day concussion IL. Callaway said he did not know whether Conforto would be activated when first eligible on Friday. ... CF Brandon Nimmo (sore neck) was a late scratch from the starting lineup. ... LHP Jason Vargas (left hamstring tightness) will throw a bullpen session Wednesday and could pitch this weekend against Detroit.
RHP Max Scherzer (2-5, 3.72 ERA), the 2016 and 2017 NL Cy Young Award winner starts for Washington and RHP Jacob deGrom (3-5, 3.98), the 2018 NL Cy Young winner starts for New York in a rematch of opening-day starters. The Mets won the opener 2-0 as deGrom struck out 10 and allowed six hits in six innings. Scherzer gave up two runs and two hits in 7 2/3 innings, striking out 12.
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