IRVING, TEXAS ? Regardless of whether Ron Dayne ever outruns his reputation as an underachiever, he’ll always be able to look back fondly at Thanksgiving 2005.

Filling in for injured Tatum Bell, Dayne rumbled 55 yards on the second play of overtime, and Jason Elam followed with a 24-yard field goal to give the Denver Broncos a 24-21 victory over the Dallas Cowboys on Thursday in the kind of tight, tense game expected in a clash between first-place teams.

Bell was a surprise scratch because of a bruised chest, and Dayne didn’t even know he’d be in the lineup until Thursday. He responded with 98 yards rushing, his most since Sept. 30, 2001, and scored his first touchdown since the 2004 opener, when the 1999 Heisman Trophy winner was still with the New York Giants.

“The coaching staff gave me a chance and they believed in me,” Dayne said. “I was glad I got this opportunity to show Coach that I wasn’t a bust.”

The game was close for more than four quarters, with the margin never wider than a touchdown. Both defenses came up with big plays and each team downed a punt inside the two. There was a close call by the officials, and the Cowboys (7-4) missed a 34-yard field goal that would’ve put them ahead midway through the fourth quarter.

Denver's Ron Dayne (33) finds the open field past Dallas' Keith Davis (29) and Aaron Glenn (26). Dayne's 55-yard run set up the game-winning field goal in Denver's 24-21 overtime victory Thursday in Irving, Texas.

Denver (9-2) never trailed in winning its fourth straight, but the Broncos were hardly in control. Their running game struggled until Dayne’s big burst and Jake Plummer threw his first interception since Week 2. Still, they improved to 3-2 on the road to maintain hopes of catching unbeaten Indianapolis for home-field advantage in the AFC playoffs.

“I guess we’re living right,” said cornerback Champ Bailey, who returned an interception 65 yards for Denver’s first touchdown. “Everything worked out tonight. … We have something special here.”

Dallas ended a three-game winning streak and, like all its other losses, this one was decided late. The Cowboys’ losses are by a combined 13 points, with the last two coming on game-ending field goals. This one gives the Giants a chance to take over first place in the NFC East on Sunday, before facing Dallas the following weekend.

“I’m disappointed with the outcome, I’m not disappointed with the effort,” Cowboys coach Bill Parcells said. “I thought we played pretty solid on defense, until that last run.”

Dayne and Mike Anderson were alternating series, and it was Dayne’s turn when the Broncos won the overtime coin toss. After opening with a pass, Plummer handed off to Dayne on second-and-three from the 39.

He bowled through the left side of the line, pulled away from would-be tackler Keith Davis around the 50 and kept going until he was dragged down from behind by Terence Newman at the six. The speedy Newman actually got to Dayne at the 10 but, carrying 245 pounds and a full head of steam, Dayne took awhile to go down.

Denver called timeout, then went straight to Elam. The kick was perfect, and the Broncos let out a huge sigh of relief.