MIAMI — Johan Santana insisted he was a bit nervous in the moments before his highly anticipated debut with the New York Mets.

Didn't look it, not one bit.

Santana struck out eight in seven dominant innings, David Wright hit a three-run double and New York opened its season with a 7-2 win today over the Florida Marlins.

"It's always good to get the first one out of the way," Santana said. "I wasn't trying to put anything in my head or anything. Just another game, another opening day, different uniform, lot of expectations. But I felt good."

If only the Mets had Santana (1-0) last September, when they blew a seven-game lead in the NL East with 17 games left. The collapse became complete when the Marlins scored seven times off Tom Glavine in the first inning on the season's final day.

But Santana — who was traded to the Mets from Minnesota this winter and signed a $137.5 million, six-year contract — dazzled today from beginning to end. The two-time Cy Young winner struck out Hanley Ramirez to begin the game and Matt Treanor to end his outing, and allowed only three hits.

"Off to a good start," Mets manager Willie Randolph said. "Santana was outstanding today. He was pounding the zone all day and I thought he threw even better than he looked, because he threw a lot of strikes and balls were kind of borderline that he didn't get. But he made pitches when he had to and it's nice to have the big horse start things for you."

Wright and Carlos Beltran each doubled twice for the Mets. Jose Reyes added two hits for New York, which has now won 30 of its last 39 openers.

Josh Willingham hit a two-run home run for Florida.

"We got the home run off him," Willingham said, "but that was about it."

The Mets took command with their biggest inning on an opening day, scoring six runs in the fourth against Mark Hendrickson (0-1).

Beltran led off the inning with a double and Angel Pagan, Mets newcomer Ryan Church and Reyes hit RBI singles. A walk to Luis Castillo loaded the bases for Wright, who began the game with a career .462 average in that situation.

No surprise, then, that his liner rolled all the way to the left-center field wall, giving the Mets a 6-0 lead. The Mets' previous biggest burst in an opener was five runs in the seventh inning in a win over the Chicago Cubs at Wrigley Field on April 5, 1979.

"I was looking for a fastball," Wright said. "He was very sneaky. His fastball got on you a little bit — but that one was left over the middle of the plate."

The Mets batted around for so long, they might've thrown Santana off his rhythm.

Santana retired the first nine Marlins he faced, then went 28 minutes without throwing a pitch while his teammates kept piling up runs. Ramirez drew a leadoff walk in the fourth and, two outs later, Willingham homered to left field.

Santana set down seven of the next nine batters, striking out five. When he walked off the field after the seventh, the decidedly pro-Mets crowd of 38,308 at Dolphin Stadium gave him a long cheer.

"He's one of the best," Randolph said. "It's a pleasure to watch him work."

With Santana out of the game, Florida tried to rally in the eighth, putting runners on second and third with two outs. Jorge Sosa, the third Mets pitcher of the inning, came on and struck out Willingham.

"When you get your opportunities, you have to cash in on them," Willingham said. "And we didn't get many."

Marlon Anderson singled and eventually scored from second after Matt Lindstrom's wild pitch in the ninth to give the Mets a 7-2 lead.

Notes: Randolph seemed baffled by a lengthy postgame line of questioning regarding Castillo not running hard on Beltran's bloop double in the first inning. "I'll chastise him later," Randolph said, tongue firmly in cheek. "I'll get on him. I'll get the whip and I'll beat him, I'll beat him later, all right? Wow, what about Santana?" ... Florida has lost 11 of 12 at home against the Mets since Sept. 11, 2006. ... Treanor, making his first opening day start, threw out Reyes — who stole 78 bases last year — at second to end the sixth. Treanor easily caught Wright trying to steal third in the seventh. ... Making his 18th straight opening-day start, a streak that began two years before the Marlins began play, Florida right fielder Luis Gonzalez was 1-for-4. ... Florida honored "Mr. Marlin," retired OF Jeff Conine, as part of the pregame ceremonies. "I wore five other uniforms, but I want to say that I always considered myself a Florida Marlin," Conine told the crowd.