WASHINGTON (AP) -- His grand slam deposited in the seats, Felipe Lopez clapped and screamed as he rounded first base, then smacked Tim Tolman's hand so hard while turning for home that the third-base coach shook off the sting.
Baseball is fun for Lopez right now, something that wasn't always the case a year ago. He's in the lineup again -- and hitting again.
Lopez tied a career high with six RBIs thanks to his first homer of the season and a two-run single, leading Washington past the struggling New York Mets 10-5 on Thursday night, the Nationals' fourth victory in their past 20 games.
"I'm me again, you know?" said Lopez, who's hitting .357 in seven games since supplanting a slumping Ronnie Belliard as the starting second baseman. "I steal bases, score runs, get on base, walk. It's exciting."
The Nationals fell behind 3-0 while being held in check through four innings by Mets starter Oliver Perez. But Washington's weak lineup -- 3.5 runs per game and a major league-low .227 batting average coming in -- broke out for three runs in the fifth, four in the sixth and three in the seventh.
"That will be able to relax some of the guys," Nationals manager Manny Acta said. "We're not as bad as we have hit so far."
Washington matched a season best with 13 hits to make a winner of Mike O'Connor (1-0), who was called up from Triple-A Columbus before the game and threw one inning of relief in his first appearance in the majors since 2006.
Lopez led the way, twice coming through with the bases loaded. He put the Nationals on the scoreboard with his single off a fastball from Perez (2-1) in the fifth, making it 3-2, then broke a tie in the sixth by homering off reliever Aaron Heilman's changeup.
"I got hurt pretty bad on a mistake," Heilman said.
Perez began the trouble in the sixth by putting two men on. Then, with two outs, Heilman entered and walked pinch-hitter Lastings Milledge -- he was dropped from the starting lineup by Acta for showing up late to the ballpark -- and that brought up Lopez.
A 2005 All-Star with Cincinnati, Lopez hit .245 last season, then lost out to second baseman Ronnie Belliard and shortstop Cristian Guzman in a three-way competition for the two middle infield spots during spring training this year.
"He never put his head down," Acta said. "He worked hard and had a good attitude."
With injuries to two left fielders, Acta put Lopez in the outfield for the first time in his career to get him some playing time. And then Lopez moved into the starting lineup for good a week ago, taking over for Belliard at second base. He also supplanted Guzman as the leadoff hitter.
"It's always good to have people on your side. But at the end of the day, you've got to believe in yourself," Lopez said. "You can have the whole world believe in you -- if you don't believe in yourself, it doesn't matter. I believe in my abilities. I'm very positive."
With the count full, Lopez drove Heilman's pitch over the out-of-town scoreboard in right-center, making it 7-3 with his fourth career grand slam, and the Nationals' first of the season.
"What matters to me is now," Lopez said, "and helping this team turn around."
Still only 7-16, the Nationals have the NL's worst record, but Acta is always looking on the bright side, and Thursday night was no different.
"By the way," Acta said, "we haven't won three out of the last 17 -- we have won two out of the last three. OK?"
The Mets, meanwhile, have dropped four of their past five games.
"We're just kind of sputtering around a little bit," manager Willie Randolph said.
Nationals RHP Shawn Hill gave up three runs through five innings in his second start of the season. Each run allowed by Hill came on a two-out single -- by Perez, Ryan Church and Luis Castillo. ... Perez was charged with five runs and six hits in 5 2/3 innings. Heilman's line was worse: two runs and three hits in 1/3 of an inning. He was followed by Jorge Sosa, who gave up three runs -- one earned -- and three hits in one inning. ... Carlos Beltran and Marlon Anderson hit solo shots for New York. ... Mets C Brian Schneider was sent back to New York and hospitalized with an infected left thumb.