"Two pitches is what it comes down to, to me," Zimmermann said. "Two bad pitches cost me the game."
The offerings he was referring to were during the first two at-bats of the sixth, when Hanley Ramirez singled and Giancarlo Stanton crushed a 412-foot home run to tie the game.
Both pitches were sliders from Zimmermann, who dropped to 0-3 in six career starts against the Marlins.
"Zimm pitched a good ballgame, he just made a bad pitch to Stanton," Nationals manager Davey Johnson said. "To get beat on that pitch was tough. He was so in control until that inning and had a low pitch count and was throwing the heck out of the ball. You just can't make mistakes in that part of the lineup."
The Stanton home run was his 11th in May and it derailed an otherwise smooth start from Zimmermann.
Prior to the sixth, Zimmermann gave up just one run -- a Logan Morrison shot to right field in the fourth -- and limited Miami to four hits. But the mistakes to Ramirez and Stanton proved costly, as the Marlins added two more hits before Zimmermann could retire a batter in the sixth, getting John Buck to strike out with runners on the corners.
Chris Coghlan then delivered a sacrifice fly to left field to give the Marlins a lead they wouldn't give up, adding another run in the seventh against reliever Henry Rodriguez.
"It's always good to do that and tie it up in that situation," Stanton said. "We kept it rolling and got two more."
Zimmermann exited after the sixth, and gave up four runs on eight hits, including the two home runs. While the righty gave up homers to Morrison and Stanton, he showed power early in the game, when he delivered a round-tripper of his own in the third.
Zimmermann took a 2-2 offering from Marlins righty Carlos Zambrano and sent it over the left-field wall, where Coghlan attempted to climb the wall to rob Zimmermann of his first career home run.
But Coghlan came down empty-handed, and Zimmermann trotted the bases -- after some confusion as to whether Coghlan made the play -- for the first run of the game.
"It's hard to see; there's so many bright objects out there and he kind of fell down," Zimmermann said. "I didn't know if he had it in the glove or not, so I had to look back and see if he caught it or not."
Washington got two more runs in the fifth thanks to three consecutive one-out hits against Zambrano. Steve Lombardozzi, who finished the day 3-for-4, and Bryce Harper hit back-to-back singles before Ryan Zimmerman drove them in with a two-run double.
In 100 career games against the Marlins, Zimmerman has 54 RBIs and 25 doubles. Lombardozzi, meanwhile, continues to impress while settling into the Nationals' lineup and batting leadoff. In his 19 starts this season, he is hitting .325 with eight runs scored, five doubles and six RBIs.
"Any player, as they get more consistent playing time, they're going to feel more comfortable at the plate," Lombardozzi said.
The Nationals got two aboard to lead off the seventh and chase Zambrano, but Harper hit a fly ball to Coghlan in left before Zimmerman grounded into a double play to end the inning and the Nationals' last threat. The Nats went hitless in their final eight at-bats to end the game and snap their three-game winning streak.
"Under the circumstances, I thought we played well," Johnson said. "Probably a little air went out of us when Stanton hit that bomb, but we battled back. ... It just wasn't meant to be. I thought our effort was real good."