The Buffalo Bills and Arizona Cardinals are surprising leaders atop their respective divisions in the NFL standings.  Meanwhile, a few of the squads we're used to seeing among the league's elite are struggling, including Peyton Manning and the Colts.  Hoping to put their slow start behind them, Indianapolis looks to climb above .500 for the first time this season when they host the Baltimore Ravens on Sunday.

Check out the NFL’s division leaders heading into Week 6. Teams like the Buffalo Bills and the Arizona Cardinals are trying to leave decades of mediocrity behind them, while familiar elite clubs like the Indianapolis Colts and San Diego Chargers are breaking down. Is there a Titans-Giants Super Bowl matchup in store? Or how about (gasp) Ravens-Eagles? It’s all up for grabs now.

Baltimore (+4) at Indianapolis
Sunday, Oct 12, 1:00 p.m. (ET) CBS
The Colts were as high as 6-point faves at the open. I would have expected even more line movement on this one given the rash of injuries the Colts defense has absorbed this week. DE Dwight Freeney (hamstring), CB Kelvin Hayden (knee) and LB Clint Session (calf) were all held out of Thursday’s practice; Hayden is out Sunday, while Freeney and Session were uncertain as we went to press. With S Bob Sanders (ankle) already out of commission until November, the Colts run defense is in major trouble against the Ravens (2-2 SU, 3-1 ATS).

The betting public is more wrapped up in Peyton Manning and his frustrating start to the 2008 campaign. Manning has a 79.2 passer rating playing behind a banged-up offensive line, and the Colts are fortunate to be 2-2 SU and ATS after last week’s improbable come-from-behind victory over Houston. Indianapolis will be able to plug some of these holes next week once players on the PUP list are eligible to return. For now, the Colts are stuck facing the top defense in the NFL, both on the ground and in the air.

Carolina (+1½) at Tampa Bay
Sunday, Oct 12, 1:00 p.m. (ET) FOX
The Panthers (4-1 SU, 3-1-1 ATS) have definitely returned to form with QB Jake Delhomme and his 90.6 passer rating; in his Pro Bowl 2005 campaign, Delhomme had an 88.1 rating and Carolina went 11-5 (9-7 ATS). Tackles Jeff Otah and Jordan Gross have resumed practice and are expected to start, giving Delhomme that much more time to work his magic. He’ll need it. The Bucs have the No. 4-ranked defense in the league in terms of efficiency.

What the Bucs don’t have is a healthy offense. QB Jeff Garcia took all the first-team snaps in Thursday’s practice and is expected to start Sunday, taking his No. 1 spot back from Brian Griese (elbow). This is actually a positive for the Bucs, since Garcia’s production levels are higher across the board and he’s a better fit in the West Coast offense. Ernest Graham (5.9 yards per carry) and Warrick Dunn (5.1 yards) could have a strong game versus the middling Panthers run defense.

New England (+5) at San Diego
Sunday, Oct 12, 8:15 p.m. (ET) NBC
Are the Patriots undervalued? They’re 3-1 SU (2-2 ATS), and aside from that Week 3 disaster against the Dolphins have looked very good with Matt Cassel (84.1 passer rating) at quarterback. That’s the kind of production Tom Brady used to provide every season until last year’s record-setting blowout, which was sparked by the acquisition of wideouts Randy Moss and Wes Welker. Cassel hasn’t gone deep too often, though, as the Patriots are bringing him along slowly with quick, short passes and a whole lot of running.

The Chargers (2-3 SU, 2-2-1 ATS) have given up a whole lot of running this year: 113.4 yards per game, leaving them No. 26 in the league in efficiency against the rush. The defense is absolutely missing LB Shawne Merriman; his replacement, highly touted prospect Jyles Tucker (hamstring), is out this week and perhaps next. Defensive co-ordinator Ted Cottrell already gets lots of heat for his vanilla 3-4 defense. It’s only going to get worse after New England’s tailbacks turn the corner on the Chargers front seven and pile up the yards Sunday night.

San Diego is hurting on offense, too. It’s obvious that RB LaDainian Tomlinson and TE Antonio Gates are playing hurt, but Philip Rivers (103.0 QB rating) has worked wonders to keep the Chargers competitive. Now he’ll have to do it without WR Chris Chambers (ankle) and perhaps WR Vincent Jackson, who “tweaked” his knee in Wednesday’s practice and sat out Thursday. This is not a good matchup for San Diego.