Detroit, MI (CBSDFW)- Following a disappointing loss to the Minnesota Vikings on Sunday night football, the Cowboys lead over the division rival Eagles has evaporated. At 5-4, the Boys are now tied with the Birds at the top of the NFC East and only sit in first place thanks to their win in the teams’ head-to-head matchup earlier this year.

With the Eagles facing a difficult task this Sunday in Philadelphia against the Patriots, Jason Garrett’s crew has a chance to get some breathing room at the top of the division if they can knock off a different NFC North team, the Detroit Lions.

The Lions, 3-5-1, are slowly watching their season slide off the rails after consecutive losses to the Raiders and Bears. Further complicating matters is the injury to starting quarterback Matthew Stafford, who is dealing with several broken bones in his back but attempting to play through them. He couldn’t make it on the field last week in the loss to Chicago, but backup Jeff Driskel filled in admirably, completing 27 of his 46 attempts for 269 yards and a touchdown.

Stream your local NFL on CBS game live with CBS All Access.

With the Cowboys traveling to Detroit after a loss and the Lions having dropped two straight, Sportsline senior NFL analyst Larry Hartstein says it’s “easy to make a case against both teams” when looking at the spread. However, there are a couple of key points to consider. The first is the Lions’ inability to stop opponents on third downs.

“The Lions have failed to cover their last four, and they give up 45% third-down conversions. That is one of the worst in football,” said Hartstein. “The Cowboys convert 51%, the highest in football.”

That disparity on third downs certainly plays in the ‘Boys’ favor, but Hartstein also notes that Dallas has not been good against the number when facing teams outside of their division this season. Of their five games played against opponents outside the NFC East so far this year, the Cowboys have covered the spread just once, against the lowly Miami Dolphins in Week 3. And, they needed a second half explosion to do it.

So what will be the biggest factor on Sunday? For Hartstein, it comes down to Stafford and whether or not he will be able to play for the Lions. The Detroit quarterback has posted career highs in both passer rating (106) and yards per attempt (8.6). He has been the driving force for the Lions offense, as their running game ranks 20th in the league, averaging under 100 yards per game. Whether or not Stafford plays will make a huge difference for how the oddsmakers see this matchup.

“Stafford didn’t practice on Wednesday, with the broken bones in his back. And we know what kind of a gamer he is, and he is going to try and play. He really looks like he is 50/50 as we record this,” said Hartstein. “But, this spread is probably going to be Dallas -3 with Stafford. If it’s Jeff Driskel, who actually played pretty decently at Chicago, it will probably be up around 9-9.5.”

The Cowboys and Lions kick-off from Ford Field in Detroit on Sunday, November 17th at 12:00 p.m. Central Time.