Wells, Harvin and that 2009 rookie debate

Beanie Wells' swollen knee and Percy Harvin's tender ankle are threatening to postpone the Wells-or-Harvin debate that began here when both were rookies.

I took up Wells' cause, figuring his style would fit perfectly as the Arizona Cardinals became more of a running team. Kevin Seifert of the NFC North blog pushed Harvin even before Minnesota acquired Brett Favre, figuring the Vikings would give the receiver plenty of chances as a return specialist.

Wells and Harvin put up nearly identical offensive yardage numbers last season: 793 rushing for Wells, 790 receiving for Harvin. But Harvin's production as a return specialist gave him a decisive edge, just as Seifert had predicted.

Injuries could affect both players when the Cardinals and Vikings play Sunday for the second time since using 2009 first-round choices on Wells and Harvin. Wells missed the first two games this season following knee surgery. An allergic reaction caused swelling in the knee this week, calling into question Wells' availability. Harvin has started all seven Vikings games to this point, but an ankle has sidelined him this week.

Wells has 69 carries for 233 yards and two touchdowns this season. Harvin has 31 receptions for 393 yards and three scores. Harvin also has a 26.0-yard average on kickoff returns, with a 95-yard touchdown.

Their career arcs have followed relatively predictable patterns. Wells' durability was a question mark coming out of Ohio State. He suffered an ankle injury in his first training camp practice as a rookie, setting back his development last season. The knee injury he suffered during the 2010 exhibition season is still affecting him. Harvin has flashed more star power and has missed only one game despite suffering some of the medical troubles that bothered him during college, including bouts with migraines.

The Vikings have done a better job utilizing Harvin's talents to this point. The knee issues Wells has suffered from this season have made it tougher for the Cardinals to lean on him as heavily. The team has also fallen behind enough to diminish the viability of the running game.

I still would have expected Arizona to become more of a power team by design, however. The Cardinals have used three- and four-receiver personnel groups more than I would have expected, particularly with injuries affecting their receivers at various points. Wells has often been at his best running with two tight ends on the field.

Career Comparison: Wells vs. Harvin