NEW YORK (AP) -- Bryce Harper by far made the most noise on Bark in the Park day.
Harper launched two long home runs, including a tiebreaking drive in the eighth inning, and also doubled Saturday to lead the Washington Nationals over the New York Mets 7-6.
About 500 dogs paraded around the warning track before the game as part of annual pooch promotion held by many teams. Harper, who owns a young chocolate Labrador retriever named Swag, enjoyed the procession.
''I saw them. It was awesome,'' he said.
Almost as impressive as his power show.
Harper hit a two-run homer to right-center in the third. He then hit the first pitch from Josh Edgin (0-1) in the eighth even farther and harder to right-center for his seventh home run.
''That one pitch came back and bit me,'' Edgin said.
The 20-year-old All-Star has four multihomer games in not quite a full year in the majors. Harper walked in his other plate appearance and is hitting .371 this season.
''He crushed a couple of balls. What a day he had,'' Nationals manager Davey Johnson said.
Harper will soon have an adoring admirer. His dog is with his family right now in Las Vegas, but Swag will soon join his owner.
''He's coming to live with me in about two weeks,'' Harper said. ''He's a great dog, I can't wait to have him.''
Adam LaRoche and Ian Desmond homered for the Nationals before a crowd of 24,325 at Citi Field. Fans paid $35 for tickets in the second deck in right field, and brought their dogs for $10.
After the game, Johnson said third baseman Ryan Zimmerman was being placed on the 15-day disabled list because of a strained left hamstring. Zimmerman didn't play Friday or Saturday, and had an MRI.
''Not going to take a chance,'' Johnson said. ''I don't mess around with hamstrings.''
Washington finished with seven hits, all for extra-base hits.
Nationals outfielder Jayson Werth petted a couple of Labrador retrievers and teammate Danny Espinosa greeted a dachshund during the parade. Werth and Espinosa later doubled.
The Mets didn't homer for the first time in eight home games this year. They do, however, have a history that links homers and dogs: Before the bigheaded Mr. Met, their first mascot was a beagle named Homer.
In 1962, Homer was supposed to run around the bases at the Polo Grounds after the Mets connected. The first time he tried to do it in a game, the story goes, he reached second base and took off on a sprint for center field.
LaRoche hit a three-run homer in the fifth that put Washington ahead 6-5. The Mets tied it in the seventh when Daniel Murphy hustled for an infield hit and scored on John Buck's two-out double, helped when Desmond bobbled the relay at shortstop.
Tyler Clippard (1-0) got four outs for the win and Rafael Soriano closed for his sixth save.
Nationals starter Gio Gonzalez gave up five runs in the fourth with two outs. He looked uncomfortable, crouching on the mound before giving up two-run singles to Collin Cowgill and Justin Turner and an RBI single to Daniel Murphy.
Gonzalez, who led the majors with 21 wins last year, is 1-1 with a 5.85 ERA after four starts.
''Just one of those moments,'' Gonzalez said. ''Go back to the drawing board.''
Craig Stammen relieved Gonzalez and struck out five in two perfect innings.
Desmond homered leading off the second against Jeremy Hefner. Harper homered the next inning and doubled in front of LaRoche's two-out home run.
NOTES: 2B Espinosa made first start since Sunday because of a bruised right forearm. ... Johnson expects Soriano will miss Monday night's game vs. St. Louis. Soriano's wife is set to soon deliver the couple's baby. ... Mets SS Ruben Tejada didn't start, a day after a Nationals player rolled over his right ankle on a slide. Tejada pinch-hit in the fourth and walked. ... Hefner made a behind-the-back stop on Kurt Suzuki's hard comebacker and threw him out from a sitting position.