The Panthers and kicker John Kasay have agreed to terms on a four-year contract extension that locks him up through the 2010 season. Kasay, 39, was scheduled to become a free agent at the end of the season. He is 16-for-16 on field-goal attempts and has hit all 18 extra-point attempts in 2008.

Cardinals' receiver Anquan Boldin caught nine passes for 63 yards and a pair of touchdowns in his return to the field on Sunday. Arizona lost to Carolina, 27-23, but got Boldin back. The receiver hadn't played since Week Four, when he suffered a sinus fracture after taking a hit from New York's Eric Smith in the end zone.

Anquan Boldin returned to practice for the Cardinals on Monday, just over three weeks after he was injured on a hit by the Jets? Eric Smith. ?I?m feeling good enough to put a helmet back on now,? he said after the light workout. The receiver was scheduled to see the doctor on Tuesday and hoped to gain medical clearance to play Sunday, when the Cardinals are at Carolina, according to an Associated Press report.

The two-back system has been all the rage in the NFL this decade, with fourteen teams having purposely installed two-back systems so far this season. We have defined a two-back system as one in which two running backs have at least 20% of their team's carries. Teams opt for the two-back system for a variety of different reasons. For example, the Lions have featured both Kevin Smith and Rudi Johnson this season because neither has been overly effective. On the other hand, the Cowboys have used Felix Jones to rest Marion Barber and provide a different look to opposing defenses. The Broncos are another extreme, with Mike Shanahan featuring three different backs prominently. Through the first five weeks of the 2008 season, more than fourteen teams technically have two-back systems, but clubs like Baltimore, Philadelphia and Pittsburgh have been forced to take the load off of their feature running back because of injury. If Willis McGahee, Brian Westbrook and Willie Parker had remained healthy, chances are they'd have more than 80% of their team's carries. The fourteen teams that have purposely installed two-back systems have a combined record of 40-25 (62%) in 2008. Meanwhile, the remaining eighteen teams have a combined record of 34-49 (41%) this season. Not surprisingly, five of the eight division leaders through Week Five featured two-back systems. Here are the teams have been sharing carries between at least two running backs this season: Two-Back Teams Team: Running Backs (% Of Carries), Record Arizona: Edgerrin James (68.1%), Tim Hightower (26.7%), 3-2 Atlanta: Michael Turner (70.0%), Jerious Norwood (25.8%), 3-2 Carolina: DeAngelo Williams (49.6%), Jonathan Stewart (42.3% ), 4-1 Dallas: Marion Barber (73.0%), Felix Jones (21.7%), 4-1 Denver: Selvin Young (42.3%), Andre Hall (28.8%), Michael Pittman (26.1%), 4-1 Detroit: Kevin Smith (61.6%), Rudi Johnson (38.3%), 0-4 Jacksonville: Fred Taylor (61.0%), Maurice Jones-Drew (38.0%), 2-3 Miami: Ronnie Brown (52.3%), Ricky Williams (45.0%), 2-2 New England: Sammy Morris (39.4%), LaMont Jordan (22.0%), Laurence Maroney (25.6%), 3-1 New Orleans: Reggie Bush (55.6%), Deuce McAllister (24.3%), Pierre Thomas (20.0%), 2-3 N.Y. Giants: Brandon Jacobs (56.0%), Derrick Ward (28.4%), 4-0 Oakland: Darren McFadden (41.4%), Michael Bush (35.8%), Justin Fargas (21.9%), 1-3 Tampa Bay: Earnest Graham (55.8%), Warrick Dunn(44.2%), 3-2 Tennessee: Chris Johnson (55.9%), LenDale White (41.7%), 5-0 RealGM Note: Percentages were calculated by dividing a running back's carries by the team's total number of carries by running backs.