ALLEN PARK, Mich. The Detroit Lions have signed defensive end Will Clarke, adding much-needed depth at the position. Clarke, who has seven career sacks in 53 NFL games, joined the team for practice on Sunday. The Lions released guard Caleb Benenoch to clear a spot on the roster for Clarke. Clarke is the fourth defensive end on Detroit's roster, joining starters Trey Flowers, Romeo Okwara and rookie Julian Okwara. Clarke played for the St. Louis BattleHawks in the XFL last year.