Answer
Bob Backlund lost the WWWF Heavyweight Championship to the Iron Sheik on December 26, 1983, at Madison Square Garden in New York City. The Sheik had been the number one contender for the title for several months, and he finally got his chance to challenge Backlund at the event. The match was a back-and-forth affair, but the Sheik eventually prevailed after applying his signature Camel Clutch submission hold.