The team already had declared Ellington out for the season. He is to undergo surgery Tuesday to repair what coach Bruce Arians described as a hernia in his hip area.
Clemons is a five-year NFL veteran who played in 72 games. He started 48 games for the Miami Dolphins from 2009 to 2013. He started all 32 games for the Dolphins his last two seasons with the team.
Clemons signed with Houston in the offseason but was released on Sept. 1.
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