UNDATED (AP) — Quarterback Jon Kitna has reported to the Dallas Cowboys and will serve as Kyle Orton's backup Sunday unless Tony Romo can recover from a herniated disc in time to face the Eagles in Philadelphia.

The 41-year-old Kitna was signed after passing a physical, two years after retiring from the Cowboys because of a back injury. Cowboys coach Jason Garrett said the deciding factor was Kitna's experience and familiarity with Dallas' offensive system.

Orton's most recent start was in Week 17 of 2011 for Kansas City in a 7-3 victory over the Denver Broncos. He has appeared in three games for the Cowboys, completing 12 of 15 passes for 129 yards.

The Eagles own a one-game lead over Dallas in the NFC East heading into the season finale, but the Cowboys will win the division with a victory at Philadelphia.

In other NFL injury news:

  • The Denver Broncos had Wes Welker on the practice field for the first time since suffering his second concussion two weeks ago. Welker was allowed to participate in Wednesday's workout on a limited basis according to the league's concussion protocol. Also returning to practice was Broncos defensive end Derek Wolfe, who hadn't practiced since having a seizure-like episode on the team bus trip to the airport on Nov. 29.
  • Chargers coach Mike McCoy says he expects running back Ryan Mathews to play against the Kansas City Chiefs despite missing practice Wednesday because of an injured left ankle. Mathews wore a walking boot to protect his ankle.
  • Packers linebacker Clay Matthews will miss Sunday's game against the Chicago Bears for the NFC North title after aggravating a right thumb injury. Matthews got hurt during a sack in Sunday's 38-31 loss to the Pittsburgh Steelers. He missed four games earlier this season after initially breaking the thumb in Week 5 in October.
  • The Saints have placed safety Kenny Vaccaro on injured reserve, officially ending his season. Vaccaro broke his left ankle in Sunday's 17-13 loss at Carolina.
  • The Detroit Lions have placed tight end Brandon Pettigrew on injured reserve, ending his season. The five-year veteran injured an ankle late in a Nov. 16 loss to Baltimore and has not practice or played since.
  • The New York Giants have placed safety Cooper Taylor on injured reserve, about two weeks after he injured his hamstring.