WASHINGTON (AP) -- Bryce Harper swung at the 91 mph pitch in the bottom of the 13th inning and could tell right away the ball would end up over the fence.
''I knew it was gone. I mean, I felt it,'' the 2012 NL Rookie of the Year said. ''I haven't felt like that in a while. I haven't got extension on a ball in a pretty long time.''
Harper's fourth homer of an injury-interrupted, trying season was a game-ending, two-run shot to the opposite field off righty reliever Carlos Torres, lifting Washington past the New York Mets 5-3 Thursday and giving the Nationals a season-high 4 1/2-game lead in the NL East.
''Wanted to put a two-seamer down and away,'' said Torres (5-5), who struck out Harper on Wednesday. ''It didn't move that much, unfortunately.''
Harper was hitting .250 with 14 RBIs in 2014 entering Thursday, with zero homers since July 18.
''Hopefully he rides that for the next couple months and (we) sail off into the sunset,'' said Ian Desmond, who walked ahead of Harper's homer.
Desmond drove in Washington's first three runs with a two-run homer in the second inning, his 18th, and an RBI single in the fourth - both off Mets starter Jacob deGrom.
So can one swing change things for Harper?
''In my mind, I'm hoping so. Definitely,'' he said.
Harper missed 57 games because of a torn ligament in his left thumb, returning June 30. He immediately caused a stir that day by publicly offering suggestions for how Williams should arrange his lineup.
This week, the morning after Harper went 0 for 4 with three strikeouts in a loss to the Mets on Tuesday, Williams was asked on radio station 106.7 The Fan whether it would be a bad idea to send Harper to the minors. When a reporter followed up during Williams' pregame news conference Wednesday, the manager vented, saying: ''The minute you think you can read my freaking mind, you're sorely mistaken.''
At the end of his postgame session with reporters Thursday, Williams offered an unprompted mea culpa, saying: ''I didn't sleep much last night. So I just wanted to apologize to members of the press for my actions yesterday.''
The Nationals now head into a three-game series beginning Friday at the reeling second-place Atlanta Braves. Atlanta was off Thursday after an 0-8 road trip against the Dodgers, Padres and Mariners.
''They're going to want our throat,'' Harper said.
Said Craig Stammen (2-4), who worked three scoreless innings for the win Thursday: ''We know these three games will be big because they're right on our tails.''
He was Washington's seventh pitcher. The Mets used eight. Closer Jenrry Mejia left after giving up two hits in his only inning of work, the 12th, and said afterward his right calf was ''just a little bit tight.''
Hours after he left the mound following his 6 1-3 innings of work, Nationals starter Jordan Zimmermann was thrilled with the way Harper ended the game.
''We're all pulling for him,'' Zimmermann said. ''Hopefully he gets out of this little rut he's in.''
Mets: About Mejia, whose right calf was taped up after the game, manager Terry Collins said: ''We'll find out more tomorrow. If it's still bothering him, he certainly won't pitch tomorrow.''
Nationals: Reserve outfielder Nate McLouth (15-day DL, right shoulder) got an anti-inflammatory injection and was ''shut down for a few days to get everything calmed down in there,'' Williams said.
Nationals: Stephen Strasburg (8-9, 3.39 ERA) faces Atlanta's Ervin Santana (10-6, 3.59 ERA) in Friday's opener at Atlanta. In 14 career starts against the Braves, Strasburg is 3-5 with a 4.04 ERA, his highest ERA against any team he's faced more than three times.
Mets: In the opener of a four-game set at the Phillies, 41-year-old righty Bartolo Colon (10-9, 4.12 ERA) makes his second attempt at career victory No. 200.