UPDATE: Dockett has torn his ACL, according to Fox Sports' Mike Garafolo.
Cardinals defensive tackle Darnell Dockett was carted off the field at practice Monday with a right knee injury, according to reports.
Dockett will undergo an MRI.
Dockett, 33, has missed just two regular season games and earned three Pro Bowl appearances over 10 seasons with Arizona, which drafted him in the third round of the 2004 draft. Dockett recorded 4.5 sacks and 36 tackles last season.
More: Cardinals Preview: Destined for Another Third-Place Finish
The Cardinals' defensive line has been plagued by injuries this preseason, with Bruce Gaston and Dan Williams missing time and Alameda Ta'amu on the PUP list as he continues to rehab an ACL injury.
This offseason, the Cardinals lost linebacker Karlos Dansby in free agency and linebacker Daryl Washington was suspended for the season after violating the NFL's substance abuse policy.
The Cardinals, who went 10-6 and missed the playoffs 2013, open the season Sept. 8 against San Diego.
- Chris Johnson & Will Green