The Redskins and Titans are playing for their postseason prospects this weekend, but their opponents — the Cowboys and Colts, respectively — enjoy guaranteed high playoff seeds and must weigh the importance of resting their stars versus preserving the continuity that put them in their favorable positions.

COWBOYS (13–2) at REDSKINS (8–7)
Sunday, 4:15 p.m.

On December 2, the Redskins lost a 16–17 game to the Buffalo Bills to bring their record to 5–7. It was their fourth straight defeat, but the team was dealing with far heavier issues. Five days earlier, star safety Sean Taylor, the victim of a home invasion, died of a gunshot wound in his Florida residence. Due to the vagaries of NFL scheduling, Washington had to play four days later, but they showed great resolve by beating the Chicago Bears. The Redskins haven’t lost since the Buffalo game, and they now control their playoff fate against the Cowboys. It’s simple: Win, and they’re in as the NFC’s sixth seed.

The Redskins also lost quarterback Jason Campbell for the season to a knee injury in the win over the Bears. Backup Todd Collins, who hadn’t started a game in a decade, hasn’t lost this year as a starter. His efficiency has been enhanced by a resurgent ground game — Clinton Portis’s first 100-plus yard rushing performance in over a month came against the Giants two weeks ago — and the outside threat of receiver Santana Moss. With Campbell under center, tight end Chris Cooley was often the most viable option. The Redskins have been solid defensively during their three-game winning streak, but the caveat is that they’ve beaten teams with suspect quarterbacks (the Bears, the Giants, and the Vikings). Defensive coordinator Gregg Williams would have a major challenge on his hands if the Cowboys played all their starters for the entire game, but Dallas has wrapped up the NFC’s first playoff seed and will measure the desire for a franchise-record 14th win with the need to have everyone healthy for the playoffs.

The Redskins offered 67-year-old head coach Joe Gibbs a two-year extension, and it’s difficult to contend that Gibbs hasn’t earned it. He turned his team’s fortunes around when most of the football world had written them off.

The Cowboys-Redskins rivalry has been one of the NFL’s greatest for a long time, but Dallas has bigger fish to fry. Wade Phillips’s team must wait to see how the wild card round shakes out while they also monitor Terrell Owens’s sprained ankle. In mid-December of the 2004 season, Owens suffered a broken fibula, but he recovered in time to catch nine passes for 122 yards in Super Bowl XXXIX against the Patriots. The Cowboys hope that Owens is still a quick healer: Their dynamic offense wouldn’t be nearly the same without him.

TITANS (9–6) at COLTS (13–2)
Sunday, 8:15 p.m.

The final game of the NFL’s 2007 regular season is also the Tennessee Titans’ last chance to back into the playoffs. And whether or not the Colts, who have wrapped up the second seed in the AFC playoffs, rest their starters entirely or not, the Titans face a big challenge — they haven’t won in Indianapolis since 2002. This year has been an uphill battle for Jeff Fisher’s team. They have struggled to stay relevant in the NFL’s toughest conference (the AFC South, which the Colts have owned in recent years), but Cleveland’s loss to the Cincinnati Bengals last Sunday put the Titans in the same position as the Redskins — a victory will earn them a postseason berth.

The Colts aside, the primary issue standing in the Titans’ way is the subpar play of quarterback Vince Young. Of quarterbacks throwing at least 14 passes per game, Young’s rating of 69.5 is the sixth-lowest in the NFL, and his 4.7 interception percentage is second-highest. The Titans rank fifth in rushing yards per game, and the offensehassurvivedontheground with Young, LenDale White, and Chris Brown. It’s the defense that puts Tennessee in the playoff hunt: End Kyle Vanden Bosch leads a very active pass rush, tackle Albert Haynesworth is a force in the interior line, and linebacker Keith Bullock is one of the game’s more underrated players.

Haynesworth, who will be a free agent in the upcoming offseason, proved his value when he missed three November games with a hamstring injury. The Titans lost all three contests and gave up an average of 160 rushing yards per game, having allowed 95.5 per game overall. For Fisher and his Titans to post their first winning season and postseason activity since 2003, they’ll have to rely on that defense.

Colts head coach Tony Dungy says he’ll play his starters for a while, but the extent to which he’ll do so is unknown. Indianapolis has been beset by injuries all season, and Dungy has to think about keeping his team fresh. Peyton Manning may see more than the one or two series he usually sees in previous season finales, but don’t expect much more — unless, of course, injured receiver Marvin Harrison returns after missing nine straight games, and 10 overall, with a knee injury. In that case, it may be more important for Manning to have some game time with his favorite receiver.

Mr. Farrar is a writer for FootballOutsiders.com.