ARLINGTON, Texas -- The only drama at the end of this one was whether rookie DeMarco Murray would set the Dallas Cowboys' franchise rushing record, a remarkable feat considering it's gone from Hall of Famer Tony Dorsett to NFL rushing king Emmitt Smith.

Murray indeed pulled it off, running through a shoddy St. Louis Rams defense for 253 yards, including an early 91-yard touchdown that got the Cowboys started toward a 34-7 victory on Sunday.

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.

"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."

As impressive as Murray's performance was, it came against the Rams, who fell to 0-6 and came in with the NFL's worst defense against the run. They had allowed 163 yards per game, more than two first downs more anyone else.

The holes were so plentiful that when Murray took himself out to catch his breath in the fourth quarter, fourth-stringer Phillip Tanner finished that drive with 35 yards on the first four carries of his career, capping it with a 6-yard TD run. St. Louis wasn't even able to exploit a line featuring a starting left guard who was unemployed as of Monday.

"It's easy to run the ball when you're not making tackles," Rams safety Quintin Mikell. "When you're not getting guys on the ground, there's not much you can do."

For Dallas (3-3), the real satisfaction was ending a two-game losing skid and emphatically breaking a stretch of 11 straight games decided by four points or less.

"It was the first one where we could take a knee to win," receiver Miles Austin said. "It's a good feeling."

The Cowboys never trailed and left no reason for team owner Jerry Jones to criticize coach Jason Garrett's play-calling -- except maybe to wonder why Murray didn't have a bigger role in the offense until this game.