Tony Romo had one of the best games of his career with a team-record 506 passing yards and five touchdowns, but his late interception allowed the Broncos to beat the Cowboys. (Tony Gutierrez/Associated Press)

Tony Romo sat at the end of a bench, his eyes fixed on the sheets in a black folder as he waited.

A few minutes earlier, the Dallas Cowboys quarterback had thrown an interception, his only meaningful error of the day, and so he spent the final two minutes passing the time and hoping for one more chance against the Denver Broncos.

That would mean a stop by his defense, which was a rare sight Sunday, or maybe a second interception by Peyton Manning, which this season has been much rarer. Instead, Romo sat there as Manning engineered his ninth scoring drive of the afternoon. When Denver place kicker Matt Prater’s field goal went through the uprights for the 51-48 win, it was Romo who made the slow walk to the center of the field to congratulate the other team’s quarterback.

“It’s funny,” Romo said without a smile afterward. “You can get over the win pretty quick and get ready for the next opponent. When you lose, it just eats at you. It grinds away at you: What could we have done? What should I have done? . . . So, yeah, this will take us some time.”

This was a particularly brutal loss for Dallas, which if nothing else Sunday made its case as the best team in the NFL’s worst division. In a contest between big offenses and struggling defenses — 99 total points, 1,039 combined yards and five possessions that ended without a score — Romo was the brightest star.

But has a game ever told the Romo story so perfectly? He is dazzling and dependable until the end, bad luck or pressure caving him in. He broke Don Meredith’s 50-year-old team record Sunday with 506 passing yards, but it will be that interception that’s remembered.

“He played as good a football game as I’ve ever seen him play,” Dallas Coach Jason Garrett said afterward.

And for 58 minutes, he was as good as any quarterback in the league — even the one on the other sideline. Romo completed passes of 79 and 82 yards, scrambling out of danger and finding open receivers when it seemed impossible. He led the Cowboys to a 14-0 lead against the unbeaten Broncos, and after Manning led his team to touchdowns on five straight possessions, Romo brought Dallas back.

“Tony throughout the ballgame just found the answers,” said Garrett, whose team is tied with Philadelphia at 2-3 and somehow the division lead.

For a long time Sunday, it seemed as if Romo would be the charmed one and not the 37-year-old Manning. The old man was terrific, his four touchdown passes perhaps overshadowed only by his first rushing touchdown in five years. But for the first time this season, he wasn’t perfect. Manning had thrown 20 touchdown passes and zero interceptions before Morris Claiborne picked him off late in the third quarter.

Romo followed with a five-play, 51-yard drive that finished with a touchdown pass to tight end Jason Witten and a 41-38 Dallas lead.

“I did not know Romo was that slippery,” Broncos linebacker Danny Trevathan said. “But you can’t go in there underestimating quarterbacks, especially in this league.”

Romo’s reputation has made it easy to undervalue him, though: Wait long enough and he’ll make a mistake. It’s the flaw in his game that has kept the Cowboys out of the playoffs since 2009 and has saddled Romo with a 1-3 postseason record. He’s just dependable enough that the Cowboys have remained committed to him but so unpredictable that he remains a polarizing figure among one of America’s widest-reaching fan bases.

Late in the fourth quarter Sunday, following another brilliant drive by Manning, it was Romo’s turn. He was sacked on first down, and on the next play, he tripped on left tackle Tyron Smith’s foot as he released a pass. Trevathan dived for the ball and held on as he hit the ground.

Romo walked toward the sideline, unbuckling his chin strap in disgust and sitting there, waiting for an opportunity for redemption. He said later he just didn’t put enough power behind the pass, likely because his footing was compromised, allowing Trevathan to make the play.

“Obviously in hindsight,” Romo said, “I’d rather do anything but what we did there.”

Perhaps luckily for Romo and the Cowboys, some team will win a division that through five weeks is a combined 5-14. Three of those wins have been in head-to-head NFC East contests.

“We have more challenges ahead,” said Garrett, whose team hosts the Washington Redskins on Sunday night.

For now, the Cowboys seem to be the most likely representatives to turn around their season, and games like Sunday’s show why Dallas is both a contender and a disappointment. Its offense scored 48 points and lost, its defense baited Manning into mistakes but never forced a punt and, most memorably, Romo finished with a 140 passer rating but cost his team the win.

“We had a chance today,” the quarterback said.

The NFL’s best quarterbacks are known for their signature moments, those snapshots that tell the story of a passer’s career, and this was Romo’s signature loss. So much promise and excitement, and when his team most needs him, he makes that mistake that sends him to the bench, his nose in a folder, waiting for a chance that never comes.

Broncos 51,
Cowboys 48