Maine struggled with his command, frequently falling behind in the count, and the Nationals tagged the Fredericksburg, Va., native for three long home runs en route to a 7-1 win before a crowd of 31,456 at Nationals Park.
"I had nothing today," Maine said. "My whole body, I mean I had nothing. It was awful. It was a waste of a day."
Nationals starter John Lannan held the Mets to a lone single through six innings before lofting his own base hit over David Wright's head in the bottom half of the frame. Lannan allowed an unearned run in the eighth before getting his fifth double play of the game, a Nationals team record. It matched a franchise mark, being the fourth time the franchise turned five double plays in one game, with the last coming on May 13, 2003, in San Francisco.
The turning point in the game, according to Mets manager Jerry Manuel, came on a zany double play in the fourth inning. After a leadoff walk by Luis Castillo, Emil Brown hit a fly ball to right, which Elijah Dukes seemed to catch. Castillo believed Dukes came up with it, and he returned to first base, but first-base umpire Derryl Cousins ruled it a trap. Brown passed Castillo rounding first base for the first out, and Castillo was thrown out at second base on a 9-3-6 relay. Lannan retired the next 11 batters, and he finished the game with 19 groundouts.
"He kept the ball down," Manuel said of Lannan. "And they got a lot of double plays."
The Nationals got a two-run homer from Adam Dunn in the first, a solo shot from Dukes to lead off the fourth and a three-run blast from Nick Johnson to chase Maine in the fifth.
Maine walked just two batters, but the timing was ill-conceived. The two free passes were issued right before Johnson's home run. Maine allowed six hits and seven earned runs, striking out just one batter.
Manuel chalked up Maine's struggles to a perceived case of "dead-arm," and suggested the right-hander's velocity was down.
"He has learned to pitch a little bit," Manuel said. "When you don't have that little extra arm speed, then the secondary stuff isn't as sharp. It might be the right selection and the right location, but it's just that little extra bite that goes on it that he didn't have tonight."
Maine, who has battled an illness in recent weeks, was in no mood to make excuses after the loss.
"You can't really tell," Maine said. "It was my whole body. I didn't have my legs under me. I had nothing. I tried to get something behind my fastball, and I didn't have it. It's a bad feeling. Instead of popping them up, they were hitting the ball out of the park like they're supposed to. It was terrible."
The Mets' lone run came in the eighth, ending Lannan's string of 11 consecutive outs. Wright singled with one out, took third on Fernando Tatis' single and scored when Dukes dropped a potential sacrifice fly off the bat of Omir Santos. The play was ruled an error, and one at-bat later, Wilson Valdez grounded into his second double play of the game.
"We had some guys being a little overanxious, and he did a good job turning the ball over," Manuel said. "That's a case of being behind early and not pressing the running game to stay out of those particular instances."
The Mets were held to four hits for just the second time this season.
Sean Welsh is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.