CHARLOTTE, N.C. – According to one report, Panthers defensive tackle Vernon Butler’s knee injury isn’t believed to be serious.

NFL Network’s Ian Rapoport tweeted Thursday that Butler’s injury is considered “just a sprain,” according to a source. Rapoport also said that Butler is scheduled to have an MRI Thursday.

Butler exited the first half of the Wednesday’s preseason opener against Houston after he was blocked by Texans’ offensive lineman Breno Gicaomini.