WASHINGTON - Shut down a healthy quarterback in December so he can have remedial offseason work? Sounds like a solution for Tony Romo.

The Dallas Cowboys are teetering toward another late-season collapse, thanks in part to Romo's decision to turn a run into a pass. Romo converted an eat-the-clock moment into a tide-turning interception in the waning minutes of last week's one-point loss to the Green Bay Packers.

Now the Cowboys, who blew a 23-point lead in that game, would be eliminated from playoff contention Sunday if they lose to the Washington Redskins and the NFC East-leading Eagles beat the Chicago Bears.

On the other hand, the Cowboys (7-7) still control their postseason chances. A victory Sunday sets up a winner-take-all regular-season finale against the Eagles Dec. 29 in Texas.

It's a familiar cliffhanger refrain. The Cowboys dropped four of their last five in 2011 and their last two in 2012, finishing 8-8 both times and a just a smidgen out of the playoffs.

Dallas coach Jason Garrett said he won't "directly" address the recent history. He doesn't need to.

"We certainly understand the situation that we're in," Garrett said, "and you have to take advantage of the opportunity."

Here are five things to notice as the Cowboys visit the 3-11 Redskins (1 p.m., Fox29), the team that actually has shut down its franchise quarterback - Robert Griffin III - so that he'll be healthy when he works on his game in the offseason:

Romo's struggles: The Cowboys QB is riding a four-game December losing streak and is 13-21 all-time as a starter in December and January. He's not the only thing holding Dallas back - the defense is the worst in the NFL - but another loss will only harden his dubious legacy as a player who falters at crunch time.

Worse for Ware: Dallas' defense has already set a team record for most yards allowed - and there are still two games to play. The Cowboys might be without their top four linebackers Sunday because of injury, putting even more pressure on franchise sacks leader DeMarcus Ware. Ware's six sacks are two shy of his career low from his rookie season in 2005.

"There is no question, and he'd be the first to tell you, that he needs to make more of an impact on the game," Garrett said.

Another backup QB: The Cowboys have lost to a pair of backup QBs (Josh McCown and Matt Flynn) during their two-game losing streak, and now they face another one. With Griffin benched, Kirk Cousins will make his second consecutive start for the Redskins.

Disappointed Dez: December collapses can really wear a player down, and it showed last week when Cowboys receiver Dez Bryant headed for the locker room before the game was over. Bryant admitted it was a "bad mistake" on his part, but there's no question the Packers loss presented a supreme test of the so-called "24-hour rule" players say they use to get over the previous game.

Home game? Cowboys fans always find ways to get thousands of tickets and make plenty of noise at Redskins home games. Washington has dropped six straight and has clinched last place in the division for the fifth time in six seasons. Yeah, it's "Dallas week," but wins and losses and rivalries have taken a back seat to the constant speculation over coach Mike Shanahan's future, testing his ability to get his players ready.

"We've got a chance to play a football team that's playing for a playoff spot," Shanahan said. "And if people don't think we're playing for anything, then they get a chance to see what we're made of."