Several feuds also formed the background for the Royal Rumble match. Virgil had served as Ted DiBiase's servant and bodyguard for several years. DiBiase treated Virgil poorly, which eventually led Virgil to turn against his employer. At Royal Rumble 1991, he attacked DiBiase after a match by hitting him with the Million Dollar Championship, a title that DiBiase had awarded himself. Virgil defeated DiBiase for the belt at SummerSlam 1991, although DiBiase later regained the title. The Undertaker was feuding with manager Harvey Wippleman. He had a series of matches against Kamala in 1992 that included a bout at SummerSlam. The rivalry culminated in a coffin match at Survivor Series 1992. The Undertaker won the match, but Wippleman vowed revenge. Tito Santana and Rick Martel had formed a tag team known as Strike Force in 1987, and they held the World Tag Team Championship together for five months. Martel walked away during a match against the Brain Busters at WrestleMania V, leaving Santana to face both opponents alone. The team split up as a result and the former partners had a lengthy feud.