But Harris, who has made his share of jaw-dropping catches this season, apparently concedes nothing to the laws of nature. He raced back as fast as he could and, just as the ball appeared certain to overtake him, stuck up the glove, ripped it from the air and tumbled to the ground.

David Wright, the Mets batter, slammed his helmet to the ground and cursed in frustration as he rounded first base. It was an appropriate display of anger in a city that has become a nightmare for New York in recent years.

Harris’ catch preserved a one-run lead for Nats starter Odalis Perez, brilliant through 7 1/3 innings with  just four hits allowed. So a Cristian Guzman ground-rule double in the fifth inning — which scored Perez — was all the offense Washington needed in a thrilling 1-0 victory over the Mets.

“That [catch] saved the game. That saved the game,” said Perez (7-10, 4.26 ERA), who let out a shout and smacked his glove as Harris trotted back to the dugout with the ball. “And a lot of good things happened tonight. When you’re playing like that – even if we’re playing the last 11, 12 games of the season – like I said before we just go out there and compete.”

The District has been hard on New York. Last year it was RFK Stadium. This time it’s Nationals Park — both the scene of excruciating losses for the Mets, who for the second year in a row are falling apart in September against the last-place Nats (58-93).

New York lost five of six games to Washington last September, a huge part of an epic end-of-season collapse when they blew a seven-game lead in the National League East on Sept. 12 and missed the postseason entirely.

The Mets (83-67), ahead by 3 1/2 games in the NL East six days ago, now find themselves in second place after the Philadelphia Phillies (84-67) beat Atlanta, 8-7, on Tuesday. New York is 1/2 game in front of Milwaukee (83-68) for the wild-card lead, but has lost four of its last five, including two to the Nats. 

Harris has thieved a win from the Mets before this season. He ranks his best catch of the year an all-out dive near the foul line in left at Shea Stadium to preserve another 1-0 win on May 15.

“I don’t know. I really don’t think that was that tough of a play tonight actually,” Harris said. “The only tough thing was when I turned around the second time and the ball was in the lights.”

His teammates and manager begged to differ. If Wright’s hit got past Harris both Brian Schneider and Jose Reyes would have scored easily from first and second base.

“Wow, you know I’m not watching the other 29 teams. But I think this guy has played the best left field this season,” said Acta. “It’s unbelievable the type of defense this guy has played for us. He comes out with one of these plays every two, three days. And I’m not talking about routine plays.”

The Nats finished with seven hits and four walks off New York starter Mike Pelfrey (13-10, 3.67 ERA), including Guzman’s RBI double in the fifth. Perez led off the inning with a double of his own to start that rally and scored on Guzman’s hit. On the mound, Perez posted his best start of the season, striking out six batters and walking none. Reliever Mike Hinckley escaped a first-and-second, one-out jam in the eighth with a ground out and then a strikeout of Ryan Church. He has now tossed nine scoreless innings since a major-league call-up Sept. 2.

Closer Joel Hanrahan was even more impressive in the ninth. He had a 3-2 count on Wright, who then fouled off five consecutive pitches. Hanrahan got the best of him on the 11th, however, earning a swinging strikeout. He then got cleanup batter Carlos Beltran to fly out and No. 5 hitter Carlos Delgado to strike out swinging. The Mets’ top five batters are now 3-for-33 in the series.

“I think Wright was hitting .900 off me in his career with probably five home runs and five doubles,” Hanrahan said. “I knew it was going to be a battle from the get-go. I just had to go right after him.”