ATLANTA — Adrian Clayborn must’ve thought he was the one replacing Ezekiel Elliott in the Dallas Cowboys’ backfield.

Clayborn spent most of Sunday running around back there, making life miserable for Dak Prescott with one of the greatest pass-rushing performances in NFL history.

A solid player but hardly a star, Clayborn set an Atlanta record with six sacks and forced a pair of fumbles to lead the Falcons past the Cowboys 27-7, a game that showed just how much Dallas missed one of its key offensive players.

No, not just Elliott.

The Cowboys were also without left tackle Tyron Smith, who couldn’t go because of groin and back injuries. Third-year player Chaz Green stepped into the spot – and had a miserable day trying to stop Clayborn.

Leaving Green grasping at air, Clayborn blew by him to force two fumbles – one of which he recovered himself by ripping the ball away from Prescott – and surpass the team record of five sacks in a game, held by Chuck Smith and Hall of Famer Claude Humphrey.

“You always envision it,” Clayborn said. “I was finally in my groove.”

He matched the second-most sacks in NFL history. Derrick Thomas, Osi Umenyiora and Fred Dean are the only other players credited with six sacks in a game, while Thomas holds the league record with seven for Kansas City against the Seahawks on Nov. 11, 1990.

Clayborn had more sacks in this contest than any other season except for his rookie year in 2011, when he had 7.5.

He came into Sunday with two sacks on the season and 22.5 over his seven-year career.

“AC went crazy today,” Falcons receiver Julio Jones said.

While Clayborn and the defense dominated the Elliott-less Cowboys, Matt Ryan threw a pair of short touchdown passes and reached 40,000 career passing yards in fewer games than any other quarterback in NFL history. Ryan has 40,073 yards in 151 games, surpassing the previous mark of 152 held by Drew Brees.

Ryan hooked up with Justin Hardy on a 3-yard pass for Atlanta’s first offensive touchdown in the third quarter this season . Early in the fourth, Ryan put the game away for the Falcons (5-4) by tossing one to Austin Hooper for a 1-yard score.

Things started promisingly enough for the Cowboys (5-4), who jumped ahead 7-0 on Prescott’s 11-yard touchdown run in the first quarter. The score was set up by Xavier Woods’ interception off a deflected pass.

Atlanta took control from there, ending Dallas’ three-game winning streak.

After Matt Bryant’s 50-yard field goal, Tevin Coleman powered over from the 1 to give Atlanta a 10-7 halftime lead.

The third quarter was a trouble spot for the Falcons, whose only touchdown in the period had come way back in Week 2 on Desmond Trufant’s fumble return. Atlanta had managed only one field goal in the third over its previous five games, a major reason the Falcons lost four of those contests.