Tony Romo (back) officially out for Week 9 against Cardinals

After being temporarily sidelined by a back injury on Monday night, Dallas Cowboys QB Tony Romo will sit out Sunday's Week 9 game against the Arizona Cardinals,

After being temporarily sidelined by a back injury on Monday night, Dallas Cowboys QB Tony Romo will sit out Sunday's Week 9 game against the Arizona Cardinals, according to NFL.com's Desmond Purnell and Ian Rapoport. Backup Brandon Weeden will start in his place.

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​Romo reportedly fractured two traverse process in his lower back when he was sacked on a blitz in the third quarter of Monday's 20-17 overtime loss to the Washington Redskins by linebacker Keenan Robinson. Romo laid on the field for a while before walking off on his own power. After having x-rays and taking a pain-killing injection, Romo returned to the game at his own insistence. He finished the game with 17 completions in 28 attempts for 209 yards and one touchdown. Weeden completed four of six passes for 69 yards and a touchdown as Romo's replacement.

According to Rapoport, it was Romo who made the decision to not play against the Cardinals.

It's important to note that the Cowboys travel to London for their Week 10 against the Jaguars, and that travel process may delay Romo's return to full action. The transverse process is a bone structure that protrudes from either side of the vertebrae; they are responsible for attaching muscles and ligaments to the spinal column.

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​Weeden, the 22nd overall pick of the Cleveland Browns in the 2012 draft, has completed 442 of 790 passes for 5,185 yards, 24 touchdowns and 26 interceptions. He was released by the team in March of this year, and signed to a two-year deal by the Cowboys soon after.

"I feel ready. I'm confident," Weeden said this week. "The uncertainty is the only thing. What's the word? We going to do this? That will come but I just have to prepare like I'm going to play and expect the unexpected."

Weeden will do his thing against a Cardinals defense that has blitzed on 47 percent of their defensive plays over the last two seasons, the most in the NFL. Arizona also uses their sub-package defense (more than four defensive backs) on three-fourths of their defensive plays this season, so Weeden will see a lot of things he's not used to. Expect a heavy dose of running back DeMarco Murray against Arizona's excellent run defense.