Receiver Trishton Jackson avoided serious injury after going down in Tuesday's practice, when he clutched his right knee in pain before getting carted off the field. Offensive coordinator Wes Phillips said Jackson has been having "a great camp," and that his season isn't over.

"No ligament damage there," Phillips said, "so that was really encouraging for all of us, including Trishton. ... He's sore, but looks like he's going to be OK."

The Vikings held a lighter walkthrough Wednesday, when running back Alexander Mattison's participation was a good sign after he left hobbled Tuesday.

Edge rusher Marcus Davenport also appeared to be limited Tuesday, and was not spotted Wednesday. Cornerback Andrew Booth Jr. also was not seen after leaving early Tuesday with a trainer.