There are seven teams that have two or fewer losses this year. But that doesn’t mean those teams are without weakness: this week at the New York Times, I look at the biggest concern for each of the top teams in the NFL:

Seattle Seahawks (8-1)

Seattle has the best record in the N.F.C. and may have the most talented team in the N.F.L. The defense has allowed just 5.0 net yards per pass attempt and is tied for the lead league with 13 interceptions, thanks to a dominant secondary. A punishing running game is complemented by one of the game’s brightest stars at quarterback, Russell Wilson, who is 12-0 at home.

But … the offensive line could cost the team home-field advantage. The Pro Bowl left tackle Russell Okung has played in two games this year after injuring his foot; he is scheduled to come back at the end of the month. Right tackle Breno Giacomini, with a knee injury, should come back in December. The team’s other Pro Bowl lineman, center Max Unger, missed two games with an arm injury and left the game last week with a concussion. As a result, the Seahawks have been sacked on 10.2 percent of their pass plays this season, the third-worst rate in the league.

New Orleans Saints (6-2)

As long as Sean Payton and Drew Brees are around, the Saints will be defined by their offense. Tight end Jimmy Graham leads the league with 10 touchdowns despite playing with a partly torn plantar fascia for the last month. Darren Sproles and Marques Colston are battling injuries, but the long-term outlook is positive for both. Brees has thrown 21 touchdown passes, second in the league behind Peyton Manning. But that’s business as usual in the bayou. More notable is a revitalized defense that ranks fifth in points allowed per game.

But … New Orleans is allowing 4.9 yards per carry, the second-worst rate in the league. The defensive coordinator Rob Ryan can confuse quarterbacks, but he cannot cure the Saints’ tackling woes. The Jets rushed for 198 yards Sunday, providing a blueprint for Saints opponents. A path to the Super Bowl probably requires beating Seattle or San Francisco, or both, two of the league’s best rushing teams. And trouble may be just around the corner: the Saints have only a one-game lead in the N.F.C. South over the resurgent Panthers. In 2012, Carolina rushed for 492 yards in two victories against New Orleans; the Saints’ defense does not seem any better equipped to stop the Panthers this year.