Dallas (1-5) began the season with hopes of a run to the Super Bowl, which will be played in its stadium in February. However, the Cowboys' slow start hurt their chances and they were dealt another blow after Romo suffered a broken left collarbone in a 41-35 loss to the New York Giants on Monday night.
While he doesn't need surgery, Romo will be sidelined for six to eight weeks. Given the way Dallas' season is going, it's possible he'll miss the remainder of the season if the Cowboys decide to be cautious with him.
"We're not going to stop right now and give up or quit or whine or even make excuses," coach Wade Phillips said. "You've just got to go forward. That's what we have to do. I think our guys will band together."
The pressure of trying to resurrect a 1-5 team to the playoffs - something only done by the 1970 Bengals - falls to Kitna, who was traded to the Cowboys in 2009 and has not started since playing the first four games of Detroit's 0-16 season in 2008.
Kitna went 16 of 33 for 187 yards and two fourth-quarter touchdowns to Dez Bryant in the loss to the Giants.
"I think he will do a good job," Phillips told the Cowboys' official website. "That's why we got him in case things like this happened. I do think it took him a while in the game because he hasn't played in games that much. I think our team will rally around this guy."
The loss of Romo could lead to owner Jerry Jones at least letting Phillips finish out the year. The embattled coach, whose Cowboys have posted the franchise's worst start since 1989 when it finished 1-15, received a vote of confidence three weeks ago, and Jones reiterated that he supported Phillips after the latest game.
"Romo getting hurt doesn't affect the way I feel about Wade," Jones said.
While the Cowboys, who are 0-3 at home, have lost their quarterback for a long period of time, the Jaguars (3-4) are getting theirs back after only a brief absence.
David Garrard has been cleared to practice after passing post-concussion tests earlier this week and is expected to play Sunday.
"I feel good," Garrard told the Jaguars' official website Wednesday. "I haven't had any recurring symptoms."
Garrard missed a 42-20 loss to Kansas City last Sunday after he was knocked out against Tennessee the previous week after 12 pass attempts. He had completed 78.6 percent of his passes with five touchdowns and one interception in the previous two games - wins over Indianapolis and Buffalo.
The Jaguars hope he can help the offense after two anemic performances in as many weeks. After totaling four turnovers in a 30-3 home loss to the Titans on Oct. 18, they had three more against the Chiefs and were held below 85 yards rushing for the second straight game.
The bigger problem was on defense after Jacksonville gave up its most points and second-highest yardage total (426) of the season.
The poor effort on defense likely led to coach Jack Del Rio's decision to bench defensive end Derrick Harvey. The eighth overall pick in 2008, Harvey has started 39 games, including 24 in a row, but has just six tackles this year.
Jeremy Mincey, who like Harvey is a third-year player from the University of Florida, will make his first career start Sunday.
"(Defensive line coach) Joe Cullen believes Mincey's earned the opportunity to be the starter this week," Del Rio said. "He said, 'I feel I need to do this for the group right now.' Joe cares very much about this group. He wants them to earn it on the field."
The Jaguars hope Mincey can boost a run defense which gave up a season-worst 236 yards and three touchdowns last week. Opponents have averaged 166.3 yards rushing the last three weeks.
The Cowboys might try to take advantage of those struggles as they try to boost their offense without Romo. They rank 30th in the run, averaging 86.0 yards per game, and had a season-low 13 carries against the Giants for 41 yards.
This is the fifth meeting between these teams and the first since Jacksonville's 24-17 win in 2006. The other three games were played in Dallas, with the Cowboys winning two.