Week 13 will go a long way toward determining home-field advantage in both conferences.

The Denver Broncos visit the Kansas City Chiefs in a game that will produce a clear front-runner for the AFC's No. 1 seed. The Seattle Seahawks host the New Orleans Saints on Monday night, and the winner will be that much closer to home-field advantage in the NFC. These are four teams with seven losses among them.

This is only the second time since the 1970 merger that the two top teams in each conference have met on the same week this late in the season. The last time this happened was in Week 16 of 2008.

The Saints and Seahawks have the most on the line. The Saints play much better at home than they do on the road, and the Seahawks have perhaps the best home-field advantage in football. If the Seahawks win, the Saints might have to concede the No. 1 seed. They would be two games behind Seattle and play two of their final four against the ever-improving Carolina Panthers.

Peyton Manning wasn't as effective Sunday night in Foxborough against the New England Patriots, so the last thing he wants to do is lose the AFC West to Kansas City and enter the playoffs as a wild card. The Chiefs and Broncos each are 9-2.

Here are the top 10 trends going into Week 13.

1. Secondary issues: Seahawks cornerbacks Brandon Browner and Walter Thurmond allegedly tested positive for a substance and face suspensions. Thurmond started serving his four-game suspension Tuesday. Browner, who is recovering from a groin injury, faces a one-year suspension. He had his hearing Monday. If he loses, it would be the seventh time a Seahawks player has been suspended since 2011, including Browner twice. Clearly, Pete Carroll has a problem in the locker room, a problem he thought was addressed when veterans stepped up and preached accountability when Bruce Irvin got a four-game PED suspension in May. On the football side, believe it or not, the Seahawks could get by. Byron Maxwell takes over Browner's spot at corner. Jeremy Lane will handle the slot. Richard Sherman is the corner on the other side. Opponents have completed 14 of 21 passes against Maxwell in the time he's been on the field, which is 15 percent of the snaps. Last year, he had five passes completed against him. Naturally, Drew Brees and Sean Payton will be trying to attack those two corners, which will put more pressure on the pass rush to prevent Brees from having time to throw.

2. Defensive attrition: The Chiefs and Broncos met Nov. 17 in Denver, and the Broncos won 27-17. A lot has changed on both defenses since then, but the Chiefs have the biggest concerns. In the second quarter of last week's loss to San Diego, the Chiefs lost Tamba Hali to an ankle injury and Justin Houston to a dislocated elbow. Their departures spelled doomed for Kansas City's defense. Without both outside linebackers, the Chiefs allowed 8.8 yards a play and 38 points in the game's remaining 32 minutes. To generate any pass rush, the Chiefs had to blitz a safety or a corner, but no one got to Philip Rivers. Hali said he'll play, but if he and Houston can't play at a high level, Manning might have the time to put up 45 or 50 points on the Chiefs. Injuries have hit the Broncos, too. Since the Nov. 17 game, the Broncos lost safety Rahim Moore to a potential season-ending leg injury and defensive tackle Kevin Vickerson for six weeks with a dislocated hip. After a 9-0 start, the Chiefs have hit a tough stretch. They played the Chargers game down a right guard and right tackle. They didn't have defensive end Mike DeVito. In the first 10 games, they had only nine missed starts for injuries. If the Chiefs can't beat Denver, their destiny is to be the top wild-card team in the AFC.

3. Brees needs the Superdome: The Saints outscore opponents by an average score of 33-16 in the Superdome. They outscore opponents only 21-20 on the road. Sean Payton has built a dome team that is dynamite, but things clearly are rougher on the road. All teams can say that, but the Saints know the importance of beating Seattle on Monday night and trying to secure home field. They are still stinging from a playoff loss in Seattle after the 2010 season to what was then a 7-9 start-up team with Carroll. Now, Carroll has assembled a roster that is loaded with talent and is directed by a quarterback -- Russell Wilson -- who has not lost a home game since coming into the league. Down the line, the Saints know they have to deal with a hot Carolina team, which is breathing down New Orleans' neck with an 8-3 record. That's for later. On Monday, the Saints will find out if their road to the Super Bowl goes through New Orleans or Seattle.