Is there an upset in the 'cards'?

Scouts Inc. gives a quick preview of Super Bowl XLIII.

Cardinals X factor

WR Anquan Boldin: While you can point to numerous X factors for Arizona, Boldin's hamstring should be healthy, and he should re-emerge as a big-time playmaker. He has only six receptions in the postseason and WR Larry Fitzgerald has had to do all the heavy lifting. Fitzgerald has destroyed every zone and man coverage in the postseason, so look for Pittsburgh to sell out and commit two defenders to Fitzgerald. This will leave Boldin in numerous one-on-one situations. Arizona QB Kurt Warner has done an outstanding job of getting rid of the ball quickly, and the physical Boldin should have plenty of opportunities in Super Bowl XLIII to take some of the pressure off Fitzgerald and make some plays with the ball in his hands.

Steelers X factor

RB Willie Parker:
He is healthier now than at any point during the season. Parker is able to explode through a crevice and use his lateral agility, which is particularly beneficial when he runs inside and then bounces outside. He doesn't catch the ball well, so Parker has to do his damage as a runner. The Steelers' offense is far more difficult to prepare for when Parker is healthy and running with authority. Balance is extremely important to the Steelers' offense because their pass protection can be a glaring weakness that can be further exposed when the defense doesn't fear the run game. However, this much-maligned offensive line is playing better right now and is jelling as a unit, despite lacking high-end starters at any of the five line positions. It also has to be noted that Parker has the home run hitting ability to change a game in a matter of seconds, as he did in the Steelers' last Super Bowl appearance.