Jackson's mobility is important

Posted by ESPN.com's Kevin Seifert
There seems to be little doubt that Minnesota quarterback Tarvaris Jackson, who sprained his right knee Saturday night at Baltimore, will be ready to play in the Vikings' season opener Sept. 8 at Green Bay.

The real question is the extent to which the injury will limit Jackson's mobility early in the season. A sprained medial collateral ligament can heal sufficiently enough to play in two weeks, but that doesn't mean the player is 100 percent. Everyone deals with injuries differently.

Those who watched Jackson last season know he was far more effective after recovering from a strained groin early in the season. Of course, multiple factors contributed to his second-half surge, and it would be inaccurate to describe him as a running quarterback. But even Jackson admitted he felt more comfortable in the pocket when he knew he could effectively run if needed.

With all of his faculties this preseason, Jackson has completed 15 of 22 passes for 200 yards and two touchdowns. Making liberal use of bootlegs and other plays designed to maximize the running threat, Jackson has compiled a 127.0 passer rating. The Vikings are hoping this injury does not slow his momentum this summer.