Rotunda and Barry Windham joined the World Wrestling Federation as The U.S. Express in 1984, during which time he would be billed as Mike Rotundo rather than Rotunda. They won the WWF World Tag Team Championship twice, first from Dick Murdoch and Adrian Adonis in January 1985. The US Express' most notable feud was with The Iron Sheik and Nikolai Volkoff, to whom they lost the title at the first WrestleMania. The US Express regained the belts in June 1985, but lost them two months later to Brutus Beefcake and Greg Valentine. Windham left the WWF soon after.