MIAMI — David Wright singled home the decisive run in the 11th inning, two shaky relievers finally protected the lead, and the Mets took a big step toward the playoffs by beating the Florida Marlins 7–6 yesterday.

Jose Reyes started the winning rally with a walk and the NL East leaders moved 2 1/2 games ahead of second-place Philadelphia, which lost 5–3 at Washington.

The Mets now return home for their last seven games of the regular season, with a magic number of five for clinching their second consecutive division title.

Carlos Delgado’s three-run homer highlighted a four-run eighth that gave New York a 6-3 lead, but Florida rallied against Aaron Heilman and closer Billy Wagner to force extra innings.

Dan Uggla’s long leadoff homer against Wagner in the ninth tied it at 6, the latest late-season flop for New York’s overworked and ineffective bullpen.

But the Mets regrouped. Reyes drew a leadoff walk in the 11th from Harvey Garcia (0-1) and went to second on Luis Castillo’s single before scoring on Wright’s single to center.

New York failed to tack on, though, and still needed three outs from its middle relievers to close it out.

Aaron Sele and Scott Schoeneweis came through. Sele got the first two outs and Schoeneweis earned his second save. Each entered with an ERA above 5.00, but they needed only five pitches to combine for a perfect 11th in a game that lasted 3 hours, 59 minutes.

Moises Alou extended his hitting streak to a club-record 27 games and threw out Todd Linden at the plate to preserve a 6-5 lead in the eighth.

The teams combined to use 16 pitchers — nine by the Mets and seven for Florida. Joe Smith (3-1) threw a scoreless 10th for the win. Jeremy Hermida had three hits and two RBIs for the Marlins, who lost three of four in the series.

There was plenty of drama in the eighth, which started with the scoreboard flashing that the Phillies were beaten by the Nationals — to the delight of many in the pro-Mets crowd at Dolphin Stadium.

Alou and Delgado gave them more to cheer.

Wright opened the eighth with a walk off reliever Justin Miller, who allowed each of the first four batters he faced to score. Alou drove in Wright with a single — giving him the longest hitting streak in the majors this year — and Delgado followed with his 24th home run for a 6-3 lead.

Florida wasn’t done, though, and made things interesting against Heilman, who walked Miguel Cabrera and Mike Jacobs to open the eighth.

Linden’s second hit brought Cabrera home to cut the margin to 6-4, and Jason Wood singled two batters later. Jacobs scored easily on the play and third-base coach Bo Porter waved Linden around, but Alou threw out Linden to preserve the lead.

Heilman escaped when Hanley Ramirez lined out to Wright with two runners on, and it was still 6-5 when Wagner — who had pitched only once since Sept. 14 because of back spasms — was summoned in the ninth to protect the one-run lead.

It didn’t last one batter. Uggla hit his 31st of the year to tie the game and give Wagner his fifth blown save in 39 chances.

Florida opened the scoring in the third on Hermida’s two-run single. The Mets tied it a half-inning later on Paul Lo Duca’s two-run homer.

Florida went up 3-2 in the sixth on Linden’s RBI single, but the inning could have been worse for the Mets. Center fielder Carlos Beltran — who bruised his knee Friday — caught Alejandro De Aza’s drive for the third out as he hit the wall in left-center.

Beltran departed an inning later.