(CBS/AP) - DeMarco Murray started this season on the bench. He's going to end it in the record books. As the Dallas Cowboys steamrolled St. Louis 34-7, Murray had his way with the Rams defense, running for a franchise-best 253 yards. Murray takes the Cowboys rushing mantle from Emmit Smith, who took it from the previous owner Hall of Famer Tony Dorsett. It's fair to say Murray had a very good day.
The running back got things started early with at 91-yard touchdown run on his very first carry of the game. The 23-year-old rookie blasted through the Rams defense off a delayed handoff from Tony Romo and never looked back.
When all was said and done, Murray ran for the most yards in the NFL this season and the ninth-most in league history. His touchdown was the second-longest run in team history, topped only by the NFL-record 99-yarder by Dorsett in January 1983. He also had the most yards ever against the Rams, replacing Jim Brown on that list.
For some context, Jim Brown set that record in 1957.
"I never thought in a million years that I'd ever have a day like this," Murray said. "This is what I've been working hard for since my Pop Warner days."
Now imagine what this guy could do if he actually started. Dallas' game plan going into Sunday was to use Tashard Choice, with Murray in a backup role, to fill in for the injured starter Felix Jones. It took Murray one carry to go from "backup" to "phenom."
Murray had 187 yards through three quarters, and the Cowboys were up 20-7. Because they wanted to run to protect the lead, it was clear that Murray would get a shot at Smith's club record of 237 yards set Oct. 31, 1993, at Philadelphia.
Murray followed with a 43-yard run that could've gone for a 73-yard touchdown had he not run out of gas along the way. He finished it 2 yards shy of Smith's mark.
"I just wanted to get down and protect the ball," he said.
The record fell on his next try, an 8-yard run. He finished with 25 carries and an average of 10.1 yards. Dallas ran for 294 yards overall, spiking a season average of 84.8 that had been among the league's worst.
To be fair, the 'Boys were up against the league's worst rushing defense in the Rams. St. Louis has given up an average of 183.8 rushing yards per game.