World Wrestling Entertainment reported Thursday that hall of fame wrestler Robert Windham, best known as Blackjack Mulligan, has died at the age of 73.

According to WWE, Mulligan was known for being a tough competitor and for wearing all-black gear.  His signature iron claw hold was feared by competitors.

A Facebook fan page posted get well wishes for the wrestler in a March 28 post. A cause of death has not been released yet.