IRVING, Texas -- Jon Kitna's season -- and possibly his career -- is over.
The Cowboys put the veteran quarterback on injured reserve Wednesday with a back injury. Kitna is in the last year of his contract, and with his family remaining in Washington for most of the season, has been contemplating retirement.
The 39-year-old Kitna, in his third season as Tony Romo's backup, hasn't played since Nov. 13 because of the injury.
With Kitna out, Stephen McGee becomes the Cowboys' backup quarterback. McGee has not played this season and has been inactive six times.
Kitna's most extensive action with Dallas came last season after Romo broke his collarbone. In 10 games, he threw for 2,365 yards with 16 touchdowns and 12 interceptions.
Kitna has thrown for 29,745 yards with 169 TDs and 165 interceptions in 141 NFL games with Seattle, Cincinnati, Detroit and Dallas.
Wide receiver Dwayne Harris was called up from the practice squad to take Kitna's spot. He opened the year on the active roster as the Cowboys' punt returner, averaging 6.6 yards. He also returned three kickoffs, averaging 24.7 yards.
He was cut Oct. 18 and signed to the practice squad a day later. He was going to be called up to the active roster last month but he was sidelined by a hamstring injury.
It's the second time in as many weeks the Cowboys have promoted a wide receiver from the practice squad, with Andre Holmes getting the call last week.
The Cowboys signed Chris Greisen to the practice squad. They made the same move last year after placing Romo on injured reserve. Greisen, who played for the now-defunct Arena Football League's Dallas Desperados, was on the active roster for the final game of the year with Kitna hurt and McGee starting, but Greisen did not play.
Costa has to pass a few more tests, as regulated by the league's concussion policy, before he can practice. If he can't play Saturday at Tampa Bay, undrafted rookie Kevin Kowalski would start.
Also, kicker David Buehler had right hip surgery, which was unrelated to the groin injury that landed him on injured reserve.
Buehler missed four games because of a groin injury he suffered Sept. 18 at San Francisco. He returned for two games against Philadelphia and Seattle but was never fully healthy and aggravated the injury again, which led to his season being cut short.
Todd Archer covers the Cowboys for ESPNDallas.com. Information from The Associated Press was used in this report.