Oakland Raiders guard Gabe Jackson will be out of action for roughly eight weeks after injuring his left MCL in Thursday's practice, sources told Vic Tafur of The Athletic.
Jackson rolled up under a teammate during a training camp session and had to be carted off the field.
The injury is a major blow to Oakland's offense and pass protection. A third-round pick in 2014, the 28-year-old quickly developed into one of the league's top interior linemen.
Denver Kirkland and Jordan Devey are expected to compete for the starting right guard spot in Jackson's absence.
