Here's another key matchup in Sunday's Vikings-Cardinals game:

Vikings OLT Bryant McKinnie vs. Cardinals ROLB Joey Porter

McKinnie often is the source of much chiding up in Minnesota, but this quietly has been one of his best seasons. He's still not an aggressive punisher and finisher in run plays. But his long wingspan and good feet make him a strong and sturdy pass protector. He has played several clean games of late. McKinnie has had only one penalty this season and has been charged with allowing only two sacks, according to STATS, Inc.

He'll square off against Porter, who for years has been one of the best pass-rushing 3-4 outside 'backers in the NFL. But his performance this season has been very disappointing, much like the rest of the Cardinals' defense. Porter has three sacks and two forced fumbles this season but has been way off in terms of creating consistent pressure compared to the past two seasons. In fact, the team has started getting Will Davis, Porter's backup, onto the field more. Davis had five tackles and a sack last week in the loss to the Buccaneers.