How long will Jackson sit?

Posted by ESPN.com's Kevin Seifert
MANKATO, Minn. -- Just got back inside after Minnesota's sole practice of the day. Quarterback Tarvaris Jackson was again nowhere to be seen during practice, but after the session he emerged from the locker room limping noticeably and wearing a brace on his left knee. He rode on a golf cart from the locker room to the team's dormitories and declined to speak with the media.

I guess stranger things have happened, but that's not the scene you typically see from a player who is close to returning to the practice field. Normally, such players are on the field working on conditioning and rehabilitation during practice. So, while Jackson is officially day-to-day, it's fair to wonder how much time will pass before the day of his return arrives.

Multiple media outlets have reported Jackson suffered a first-degree sprain of the medial collateral ligament in his left knee during practice Saturday morning. But coach Brad Childress refused to confirm that diagnosis. Childress said Sunday "there is a chance" that Jackson could be on the field for a full-pads practice Monday morning, but that chance seems pretty low.

Childress again reiterated that he has no plans to sign another quarterback, leaving him in an unusual situation with only two arms in camp. I interpreted that to mean Jackson would be back on the field within days, but Childress said Sunday he is simply embracing the opportunity to give Sage Rosenfels and John David Booty extra snaps.

(Offensive coordinator Darrell Bevell, a former University of Wisconsin quarterback, has been filling in for some individual drills.)

"I just see those guys improving as we go," Childress said. "You put a premium on reps. Guys fight for reps, typically, and these guys are getting elevated reps. Neither one of them are turning their back to it. They don't want somebody else to get here and take these."

What does all this mean? First and foremost, Rosenfels is getting a very fair opportunity to catch up with Jackson in terms of growing familiar with the offense and his receivers. Whether this proves to be the turning point in their competition is a separate issue. (Jackson seemed to enter camp with a slight edge.) For now, Rosenfels has to be thrilled with the extended work he's getting.

For what it's worth, Rosenfels has looked sharper with each practice this summer. Sunday, he drilled a nice and appropriately high pass to tight end Visanthe Shiancoe in the back of the end zone during a red-zone drill.

Secondly, it seems fortune has put Jackson in a tough spot. It's always possible the Vikings are hiding a more significant injury. But if Jackson truly has a first-degree sprain of his knee, he needs to find his way back to the field soon. As the old saying goes, you can't make the club in a tub.