McClain agreed Wednesday with the Cardinals on a one-year contract, Vaughn McClure of ESPN.com reports.
McClain started five of 13 games he spent with Washington last season and finished with 17 tackles and a sack. The 30-year-old may not be the same player he was during his prime days with Dallas from 2014 through 2016, but McClain could still serve as a quality part of the defensive-line rotation in Arizona.