MIAMI -- Giancarlo Stanton took a lusty swing with his pink bat, then paused a moment to admire his first game-winning grand slam before settling into a home run trot.
"That's one of those no-doubters," he said. "It's good I could stand and watch it."
The walk-off victory was the second in the three-game series for the Marlins, who have won 10 of their past 12 games, thanks mostly to their rotation.
"We're where we're at because of our pitching," said catcher John Buck, who hit a tying homer in the seventh. "It's kind of nice to have the bats speak up a bit."
The Marlins trailed 4-2 when Emilio Bonifacio led off the ninth with his second triple of the game against the struggling Francisco (1-3). Buck walked and pinch-hitter Greg Dobbs followed with an RBI single.
Francisco was then replaced, and he walked slowly toward plate umpire Todd Tichenor, hollering angrily. Manager Terry Collins stepped between Tichenor and Francisco, who was ejected even though he was already out of the game.
Francisco waved his index finger and then his cap at the ump before finally heading to the dugout, his closer's job in jeopardy.
"I thought I was hitting my spots really good, and I didn't get a call," Francisco said.
"Any time you see the other team lose their cool like that, you know we're in the driver's seat," Stanton said.
When Francisco's tirade ended, the Mets' meltdown continued. Manny Acosta replaced Francisco, and Jose Reyes' sacrifice fly made the score 4-all. After a popup, Hanley Ramirez walked on a 3-2 pitch and Austin Kearns was hit by a pitch to load the bases.
Stanton's Mother's Day bat then closed out the victory, launching the first pitch over the left-center wall near the animated home run sculpture for his seventh homer, and sixth this month.
At first, Stanton said, he didn't hear the explosion of noise from the crowd of 26,401.
"It's a weird feeling," he said. "It's more like silence where all you see is the ball flying, and once you start going, you start to hear the big roar by everybody and the excitement."
After rounding the bases, Stanton tossed his helmet 20 feet high before hopping into a sea of jubilant Marlins at home plate. Teammate Logan Morrison gave the 245-pound slugger a celebratory hoist.
"I didn't know if his knees were going to hold out," Stanton said.
The walk-off win was the fifth for the Marlins in 14 games in their new ballpark. The Mets closed out a 4-2 trip against division opponents, with both losses coming on the game's final swing.
"We didn't finish the way we were hoping to finish," Acosta said through a translator. "It's a little tough to swallow."
The Marlins climbed two games above .500 even though they're batting just .204 with runners in scoring position, worst in the majors.
"We're still not close to our full potential," Stanton said. "Once it clicks for everybody, we're going to be scary."
Struggling reliever Heath Bell (2-3) earned the victory despite giving up two runs in the top of the ninth and drawing scattered boos when the inning ended. Mets pinch-hitter Justin Turner broke a 2-all tie with a two-out, two-run double off Bell, whose ERA rose to 10.03.
"I liked the way he threw," Marlins manager Ozzie Guillen said. "He just made one bad pitch."
Bonifacio led off the seventh with a stand-up triple, and Buck followed with his fourth homer.
Carlos Zambrano pitched seven innings and limited the Mets to two runs, one earned, which lowered his ERA to 1.88.
"It was important to keep the game close, do my job and let my teammates do their job," Zambrano said.
Mets 1B Ike Davis was scratched from the starting lineup with flulike symptoms. He pinch-hit and grounded out to end the seventh with runners at second and third. ... Mets RHP R.A. Dickey said he felt fine one day after being hit on his right wrist by a pitch. He threw another two innings after being hit and earned his fifth victory. ... When David Wright singled in the fourth, he improved to .154 lifetime against Zambrano (4 for 26) with 12 strikeouts. ... The retractable roof was closed for all three games in the series. ... The Marlins, who begin a two-game series Monday against Pittsburgh, beat the Pirates in all six meetings last year.