IRVING, TEXAS ? Jay Fiedler took the first snap, dropped back and threw deep to Chris Chambers. While pass interference prevented them from hooking up, the theme was set.

Fiedler and Chambers connected on three touchdown passes and Fiedler ran for another score, leading the Miami Dolphins past the Dallas Cowboys, 40-21, Thursday in a much higher-scoring game than expected from the NFL’s two best scoring defenses.

“We talked all week about how we needed this win, and they came out and made it happen,” Dolphins coach Dave Wannstedt said.

In his first start since Oct. 19, Fiedler was nearly perfect. He was 14-of-17 in the first half, then just 2-of-3 in the second half when the Dolphins opted to protect a big lead by handing off to Ricky Williams.

The former University of Texas standout responded with 104 yards, putting him over 1,000 for the season.

For all the offensive firepower displayed in Miami’s highest-scoring game since getting 49 in the 2002 opener, the biggest play came from the defense.

On the third snap of the second half, with Dallas down just nine, defensive end Adewale Ogunleye ticked the ball away from quarterback Quincy Carter and Jason Taylor returned it 32 yards for a touchdown to make it 30-14.

Miami (8-4) is 11/2 games behind New England in the AFC East and 11/2 games ahead of Denver and Cincinnati for the conference’s final wild-card spot.

Miami receiver Chris Chambers (84) accepts congratulations from quarterback Jay Fiedler (9) and Donald Lee after making his third touchdown catch of the game. The Dolphins defeated the Cowboys, 40-21, Thursday in Irving, Texas.

The Dolphins have won three straight and are 5-1 on the road, the kind of momentum they need considering their history of disastrous Decembers and a schedule that could set them up for another: at New England a week from Sunday, then home against Philadelphia.

“We’re definitely happy with the win, but we’re not satisfied,” Taylor said. “We know we have to stay poised for the next four games. We feel we’re a different football team now than in years past. We think that’s going to lead to success in December.”

The Cowboys (8-4) lost for the third time in six games, making the kind of mistakes that coach Bill Parcells hates most. With errors on offense, defense and special teams, the only person who might escape criticism is Richie Anderson, who had the first two-touchdown game of his 11-year career.

“We had no chance at a win,” Parcells said. “This team does not have the maturity for this kind of situation. We have young players who do not understand what’s going on. … We were just awful.”

Dallas fell out of a first-place tie with the Eagles in the NFC East, and out of a four-way tie for the best record in the conference.