McClain became a free agent in September when the New England Patriots released him in their final roster cutdown.
McClain was originally selected by the Panthers in the seventh round of the 2010 NFL Draft. He played in all 16 games and made two starts as a rookie but was released at the end of training camp in 2011.
McClain signed with the Jacksonville Jaguars in December of the 2011 season but did not play in any games. He then joined the Atlanta Falcons and was a contributor from 2012-14, starting 15 of 47 games played and recording 186 tackles and three interceptions.
With McClain in the fold, the Panthers now have five cornerbacks on the active roster. He joins