Coach Mike LaFleur said Thursday that Bisontis' left knee injury appears to be serious, Theo Mackie of The Arizona Republic reports.
"Not good," LaFleur said following Thursday's preseason matchup against the Raiders. Bisontis had to be helped off the field in the second half and took a cart to the locker room. The second-round rookie was expected to push Isaiah Adams for the starting gig at right guard at some point this season.