WASHINGTON -- Eric Campbell was between first and second base when he slammed his blue New York Mets helmet to the ground in the fifth inning Monday.

The Mets first baseman had good reason to be upset, as Washington Nationals center fielder Michael A. Taylor robbed him of extra bases and most likely two RBIs with a fine running catch on the warning track.

Strong defense was the theme of the night for the Nationals, whose glove work helped starter Gio Gonzalez get through six innings in a 7-2 win over the Mets.

"I thought it was at least off the wall, maybe top of the wall," Gonzalez said of the catch by Taylor. "I couldn't be more happy to see Mikey T making a nice play like that. It's tough to keep your emotions in check, but when a play like that happens, you gotta show love where love is due."

Washington third baseman Yunel Escobar made several nice plays, and the Nationals flashed leather in the eighth inning as well.

"They made two great plays," said Mets manager Terry Collins, referring to the gems by Taylor and Escobar. "They run some athletes at you. Heck of a play" by Taylor.

Washington manager Matt Williams was also impressed by Taylor, who had some troubles in the outfield early in the year.

"He went a long way, and that wall comes up quick," Williams said. "But it was a perfect read, perfect angle and he was able to run it down. When he gets going after three or four steps, he's really going. He covers a lot of ground out there."

At the plate Washington shortstop Ian Desmond, hitting .204 at game time, smashed a two-run homer in the eighth to give the Nationals a cushion at 7-2.

Desmond said he recently ran into Cal Ripken Jr., who told Desmond about his struggles early in the 1993 season.

"That kind of gave me a little bit of hope," Desmond said.

The Nationals were able to score five runs (four earned) in seven innings off Mets starter Matt Harvey, who had not pitched since July 11.

"I don't think they had anything to do with it," Harvey said of the long layoff. "Everyone is coming off the same amount of rest. I am not using that as an excuse."

"A lot was made about this road trip and he was jacked up because of it," Collins said of Harvey. "I think he over-threw a little bit. He knew he had to give us innings" after the Mets played 18 innings Sunday.

"He kept us in the ballgame," Collins added.

The first-place Nationals (50-41) extended their lead to three games over the second-place Mets (48-45), who have lost their last three games to Washington.

Gonzalez (7-4), who gave up six hits and two walks, was making his first start since July 10 at Baltimore and just his third this month. He was able to get the better of Harvey (8-7), who has allowed 10 runs in his last three starts.

Matt Thornton threw a scoreless seventh for the Nationals.

Casey Janssen came on in the eighth for the Nationals, and he also benefited from strong defense as right fielder Bryce Harper caught a liner off the bat of second baseman Wilmer Flores for the first out.

Then catcher Jose Lobaton made a fine catch against the railing near the Mets dugout on a pop foul hit by left fielder John Mayberry Jr. The third out of the inning came when Janssen deflected a ball hit up the middle by center fielder Juan Lagares, and the Nationals got a force at second to end the inning.

Lagares had two hits and scored a run. Washington second baseman Danny Espinosa had two hits and scored twice, and Clint Robinson, the first baseman, had two hits and two RBIs.

Harvey entered the game having thrown 16 scoreless innings in a row against the Nationals. But the streak did not last long as third baseman Yunel Escobar had an RBI single in the first to score Espinosa.

Harper, who had walked, scampered home from third to make it 2-0 after Escobar got caught in a rundown for the second out as he tried to advance on a pitch in the dirt by Harvey.

The Nationals scored three more in the third to make it 5-0 against Harvey as Robinson had a two-run double. Robinson scored on the second error of the game by third baseman Daniel Murphy.

The Mets cut the lead to 5-2 in the fourth as Harvey had a two-out, two-run bloop single to right after the Nationals intentionally walked catcher Anthony Recker, who was hitting .140, to get to Harvey.

NOTES: Mets RHP Jacob deGrom (9-6, 2.14) will try to build on his All-Star success when he pitches Tuesday in Washington. He will face RHP Joe Ross (2-1, 2.66), who has been with Triple-A Syracuse after making three starts earlier this season for Washington. ... The Nationals called up RHP Abel de Los Santos from Double-A Harrisburg on Monday and sent RHP Blake Treinen to Triple-A Syracuse one day after he gave up four runs in the ninth to the Dodgers. The Nationals also transferred OF Jayson Werth (wrist) to the 60-day disabled list to make room for de Los Santos on the 40-man roster. ... The Mets called up C Anthony Recker from Triple-A Las Vegas and sent C Johnny Monell to Las Vegas. Recker was in the starting lineup Monday, hitting eighth. ... Mets RHP Matt Harvey entered Monday with an ERA of 0.68 in his career against Washington in six starts.