WASHINGTON (AP) -- The Philadelphia Phillies are sick of wet weather, tired of waiting around and not terribly happy about losing.
After nearly six hours of rain delays in the past four games, the Phillies lost in improbable fashion for the second time this weekend.
Ian Desmond hit a tying homer with two strikes and two outs in the ninth inning, then Jonny Gomes was nicked by a pitch from Brad Lidge with the bases loaded in the 10th Sunday, giving the Washington Nationals an unlikely 5-4 win over Philadelphia.
The Phillies have the best record in the majors. The Nationals, however, topped them with a six-run rally in the ninth Friday and came back to win again.
"It was kind of a soggy week, but you still got to go out there and get people out," Lidge said.
An RBI single by Michael Martinez put the Phillies ahead 4-3 in the ninth this time. Philadelphia reliever Antonio Bastardo struck out the first two batters in the bottom half before Desmond connected on a 1-2 pitch for his fifth homer.
Ryan Zimmerman , who hit a game-ending grand slam on Friday night, started the 10th with a leadoff double against Lidge (0-1). Michael Morse was walked intentionally and Jayson Werth , after striking out three times, singled to load the bases.
Danny Espinosa fanned for the first out. Gomes was 0 for 4 before getting plunked on his left elbow by a 1-0 pitch to win it.
"In a 162-game schedule, you're going to give it up every now and then," Phillies manager Charlie Manuel said.
Sean Burnett (4-5), the sixth Washington pitcher, pitched a scoreless 10th.
The win broke a streak of eight straight winning road series by Philadelphia.
"Any time you can beat what I consider probably the best team in baseball, it's a plus," Nationals manager Davey Johnson said.
"We had them on the ropes a couple of times. They had us on the ropes, and we came back," Johnson said. "There's just no give up in this ball club. It's always fun to beat the best."
Washington got off to a 2-0 lead in the first off Roy Halladay . Desmond's leadoff double set up Zimmerman's sacrifice fly and Espinosa's run-scoring single, his first RBI since July 17.
Carlos Ruiz homered off Chien-Ming Wang in the second, tying it at 2. Chase Utley 's ninth home run put the Phillies ahead 3-2 in the third.
With two outs in the top of the sixth, lightning and heavy rain caused a delay of 1 hour, 11 minutes. Friday's game featured a 2 hour, 22 minute stoppage, and Thursday's against Arizona was halted for 2 hours, 17 minutes.
On track for his NL-leading 16th win and fourth this year against Washington before the rain came, Halladay allowed two runs and seven hits in five innings, striking out five and hitting a batter.
"It's definitely frustrating. It's not much of a game plan because you can't really map it out. It's not ideal. It kind of messed us up for about a week now. I'll be glad when the weather moves out," Halladay said.
"As a starter to be stuck going five innings, it's never fun."
When play resumed, Tom Gorzelanny replaced Wang and faced one batter.
After the delay, Halladay was replaced by Michael Schwimer , who made his major league debut. He allowed a home run to Espinosa on the second pitch he threw.
Schwimer pitched three innings and struck out four. The product of nearby Fairfax, Va., left 60 tickets and received 175 text messages this weekend, and was one pitch away from his first major league win. He didn't want to hear it.
"There's no smiley face. There's no wouldas, couldas, shouldas. We lost the game," Schwimer said.
In his fifth start since missing more than two years after shoulder surgery, Wang allowed three runs and five hits. He struck out four and walked one.
NOTES: Phillies SS Jimmy Rollins left in the third inning with a strained right groin. He'll have an MRI on Monday morning. ... Zimmerman has reached base in 27 straight games. ... Espinosa had three hits ... Philadelphia released RHP Aaron Heilman and OF Jack Cust , who had both recently been signed to minor league contracts. ... LHP Cliff Lee (13-7), who has won four straight games, is scheduled to start Monday night for the Phillies against New York. LHP Jonathon Niese (11-10) will pitch for the Mets. ... LHP Ross Detwiler (1-3) will start Monday for Washington. LHP Joe Saunders (8-10) is scheduled for Arizona.