Arizona Cardinals defensive tackle Darnell Dockett suffered a torn ACL during Monday's practice and will be lost for the season, the team announced on its website.
Dockett, who will undergo surgery, injured his knee on a pass play during an 11-on-11 period and was carted off the field.
Dockett has been remarkably durable, missing just two games during his 10-year pro career, all as a starter for the Cardinals.
A three-time Pro Bowler, Dockett started all 16 regular-season games last season, when he had 4.5 sacks.
Dockett's loss is a significant blow for the Cardinals. They lost linebacker Karlos Dansby in free agency, and will be without suspended linebacker Daryl Washington. It is uncertain when safety Tyrann Mathieu will return from his injury.