They relied on a stout defense, a jury-rigged offense and a pinch of serendipity to reach the Bowl Championship Series title game Monday night.

But in a 41-14 mauling of top-ranked Ohio State, the No. 2 Gators left little to chance.

Led by the brilliance of the senior quarterback Chris Leak, the boundless creativity of the offensive coordinator Dan Mullen and the dominance of defensive end Derrick Harvey, Florida stunned college football by blowing the undefeated Buckeyes off the field.

The victory completed one of the most unlikely runs to the national title in recent college football history. Coach Urban Meyer’s Gators grinded through the regular season with a collection of close victories, and they would not have made it here if Southern California had not been upset by U.C.L.A. on the regular season’s final day.

But once they got here, the Gators (13-1) appeared undaunted. The victory secured their second national title in football, and it made Florida the first university to hold football and men’s basketball national titles at the same time.

The Buckeyes (12-1) had the country’s top defense, the Heisman Trophy winner in quarterback Troy Smith, and the nation’s No. 1 ranking from the start of the season.

But this game proved to be a microcosm of their season, starting with a bang and ending with a thud. Ted Ginn Jr. returned the game’s opening kickoff 93 yards for a touchdown. From that point, though, almost nothing went right for the Buckeyes.

Ohio State, which had not played since Nov. 18, set up Florida’s first two touchdown drives with personal foul penalties, set up the next two with turnovers and never got Smith in rhythm.

Smith finished the game 4 of 14 for 35 yards, with an interception, and he had minus-29 yards rushing on 10 attempts. Ohio State had trailed after halftime just once during the regular season, and the Buckeyes never looked comfortable trying to scrape back from the 20-point halftime deficit.

“They moved the ball down the field all season on tape,” Florida cornerback Ryan Smith said, “but when they saw our front four, they couldn’t do anything about it.”

Troy Smith said: “Not everything in life is going to go the exact way you want it. I don’t have any regrets, though. I really don’t. We came out and fought. We came up short.”

With all that dominance, there were a few dollops of good fortune for Florida. The oft-ridiculed place-kicker Chris Hetland, who had made only 4 of 13 field-goal attempts all season, knocked in first-half kicks from 42 and 40 yards. Also aiding Florida was a first-quarter ankle injury to Ginn, who said he was injured celebrating his touchdown. Ginn did not play the final three quarters and was on crutches in the second half.

But history will best remember the lopsided tenor of the game, which Leak set by leading near-flawless touchdown drives of 46, 34 and 71 yards on Florida’s first three possessions. Leak’s accuracy — he completed his first nine passes and 25 of 36 for 212 yards and a touchdown — combined with the ingenuity of Meyer’s spread offense, led to the offensive onslaught.

Leak entered Florida as one of the nation’s top high school recruits and was the starter midway through his freshman season. He had an up-and-down career, though, and he was forced to endure boos from the fans in Gainesville this season.

On Monday, he lived up to his advance billing.

“He was unbelievable,” said Mullen, the offensive coordinator. “This is what he came here for. He came here to win championships, and that’s what he did tonight.”

Ryan Smith said: “A lot of people don’t realize he’s in the best league, playing against the best defense. He played great tonight.”

Three different players lined up at quarterback in Florida’s first eight offensive snaps. The Gators used reverses, pitches to wide receivers and draw plays to keep Ohio State off balance.

Florida’s four first-half touchdowns showcased its offensive diversity, as the Gators picked apart a defense that led the nation in scoring defense, allowing 10.4 points a game.