Washington Redskins linebacker Reuben Foster reportedly tore the ACL in his left knee on the third rep of organized team activities Monday and is likely to miss the entire 2019 season.

Foster was seen pounding the ground with his arm in frustration and had to be carted off the field, ESPN reported. Foster is reportedly set to undergo an MRI on Tuesday to determine the extent of the damage to his knee.

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“I don't know how to process it,” Redskins coach Jay Gruden said after the practice. “We've had some bad luck over here for the last couple years, but this one here takes the cake because this was a non-contact drill and there was no contact involved in it. He just landed funny. But we have to move on. We have to get guys ready to play that are here. We've got to do the best we can to get Reuben healthy again and move on.”

Washington Redskins linebacker Reuben Foster rides a cart off the field after suffering an injury during a practice at the team's NFL football practice facility. (AP Photo/Patrick Semansky)

Washington Redskins linebacker Reuben Foster rides a cart off the field after suffering an injury during a practice at the team's NFL football practice facility. (AP Photo/Patrick Semansky)

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Gruden said the injury occurred on a “jog-through.” ESPN reported Foster suffered the tear after accidentally stepping on the foot of an offensive lineman.

The Redskins claimed Foster off waivers in November, two days after the San Francisco 49ers released him following his arrest in connection with a domestic violence allegation.

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The charges against Foster were later dropped and the NFL decided not to suspend Foster.