Vulnerable defenses have plagued the Dallas Cowboys and Minnesota Vikings, with especially poor showings leading to losses for both clubs last week.
Sunday's meeting in Dallas appears to favor the Cowboys, who have compensated with one of the league's highest-scoring offenses. In contrast, Minnesota didn't even decide until Friday that Christian Ponder would be under center trying to improve an ineffective attack.
Neither team has had much success stopping opponents, with Dallas' 422.5 yards allowed per game ranking last and Minnesota 30th at 401.6. Both teams failed to provide reason for encouragement with their worst defensive performances of the season last Sunday.
Dallas (4-4) surrendered 623 yards in a 31-30 loss at Detroit - the 11th-highest total in NFL history - including the second-highest single-game receiving yardage total to Calvin Johnson (329). The Cowboys gave up a six-play, 80-yard drive in 50 seconds, capped by Matthew Stafford's winning one-yard touchdown run with 12 seconds left.
A number of injures in the secondary didn't help. Starting safeties Barry Church and J.J. Wilcox were out, though Church is expected to play Sunday while Wilcox remains out. Cornerback Morris Claiborne, however, will miss this game and possibly one more due to a hamstring injury suffered against the Lions.
The Cowboys have some fine-tuning to do on offense, too, with Tony Romo completing less than 50 percent of his passes for the first time since 2009 last week. However, he threw for three touchdowns as Dallas scored at least 30 for the fifth time this season.
Frustration from the defense's late collapse seemed to spill over to the rest of the team, with receiver Dez Bryant finding himself in a shouting match with various teammates and coaches on the sideline shortly after Stafford's decisive score. Coach Jason Garrett and owner Jerry Jones have since downplayed the significance of Bryant's outburst.
"When you put your guts out there for three hours, collectively, sometimes it's hard to swallow those kinds of defeats," Garrett said. "What we need to do as a football team is learn from what just happened and find a way, in all three phases, to win this kind of game, and do what we need to do to win the game."
The Vikings (1-6) are in considerably more dire straits, matching their loss total of last year with a 44-31 defeat to Green Bay last week. Minnesota gave up a season-high 182 rushing yards and every Packers possession ended with points except for their last drive, which concluded in the victory formation.
Opponents are converting a league-high 51.0 percent of the time on third downs against the Vikings after Green Bay went 13 for 18.
"You've got to look at how we're doing it, what we're doing schematically, and also the people that you're asking to do certain things," coach Leslie Frazier said. "Can they get it done? Do we need to be doing something different based on the people that we're asking to execute the defense?"
Frazier will at least have the services of one of the league's best defensive ends with Jared Allen staying put after speculation that he would be moved prior to the trade deadline Tuesday.
Frazier announced Friday that he would go with Ponder over Josh Freeman as his starting quarterback. Ponder was 14 of 21 for 145 yards against Green Bay with Freeman sidelined due to a concussion, though it appears Freeman would be able to play Sunday.
"I don't know if there's any one thing I can point to and say why it's Christian and Josh in this determination," Frazier said earlier in the week. He now says Ponder gives the team the best chance to win.
Ponder may want to target Greg Jennings, who has caught 24 passes for 327 yards and two TDs in four career games against Dallas.
An abysmal passing game that ranks 30th with a 69.6 rating has limited opportunities for Adrian Peterson, who has 150 yards on just 36 carries over his last three games. Opponents have been able to key on the star running back with little fear of being beaten deep.
The Cowboys hope to get their own running game going with the expected return of DeMarco Murray, who has missed two contests with a sprained left knee. Murray, who had run for scores in three of his last four games, faces a Vikings team that has allowed nine rushing TDs - second most in the NFC.
Dallas is 11-0 all-time when Murray gets 18 or more carries.
Minnesota holds an 11-10 series edge while winning five of six, the most recent of which was a 24-21 home victory Oct. 17, 2010.
Romo is 1-1 in two starts against the Vikings, completing 77.5 percent of his passes for 497 yards, four TDs and two picks.
The Cowboys placed guard Brian Waters on injured reserve Saturday after the six-time Pro Bowler suffered a triceps injury last week.