A source told ESPN.com that Vikings’ quarterback Tarvaris Jackson suffered a sprain MCL in Minnesota’s 23-15 victory over the Ravens on Saturday.

The MCL injury could keep Jackson out of the Vikings’ preseason game next Saturday against the Steelers but the injury isn’t considered serious enough to sideline him for the start of the regular season.

Vikings coach Brad Childress labeled the injury a contusion. Jackson was hit in the knee while making a run toward the right sidelines in the first quarter of the game.

Jackson, who was seven of 11 passing for 82 yards, stayed in the game a couple of plays before the pain in the knee forced him to the ground.

Viking fans can probably breath a sign of relief, but Jackson has had knee problems before. This is arguably Jackson’s make or break season and with such high expectations, it would be a shame if he wasn’t healthy to start the season. Hopefully this report is right and the injury isn’t serious.