World Wrestling Federation (1993–1996)
In 1993, Nash left WCW, signing a contract with the World Wrestling Federation at the request of Shawn Michaels. Nash made his WWF debut at a house show on June 6, 1993, assisting Michaels in defeatingMarty Jannetty for the Intercontinental Championship. Nash was given the character of "Diesel", the heelbodyguard of Michaels, dyeing his hair and beard black in the process. In January 1994, Diesel appeared at the Royal Rumble, eliminating seven men in under 18 minutes of in-ring time. Diesel won the Intercontinental Championship from Razor Ramon, following interference from Michaels on the April 13, 1994 edition of Superstars. The duo of Diesel and Michaels defeated The Headshrinkers to win the WWF Tag Team Championship on August 28, making Nash a double champion. The next night, Ramon defeated Diesel at SummerSlam to regain the Intercontinental Championship. The alliance between Diesel and Michaels dissolved after Survivor Series, and Diesel became a babyface.
On November 26, Diesel defeated Bob Backlund for the WWF Championshipat Madison Square Garden in an eight-second squash match.[14][19] Michaels was irate about his former bodyguard having beaten him to the WWF Championship and was sufficiently motivated to win the 1995 Royal Rumble, earning himself a title shot at WrestleMania XI. At WrestleMania XI on April 2, Nash, accompanied to ringside by actress Pamela Anderson (who was supposed to valet for Michaels), defeated Michaels to retain the title. After the match he left the ring with both Anderson and Michaels' replacement for her, Jenny McCarthy. The next night on Monday Night Raw, Michaels was betrayed by his new bodyguard, "Sycho" Sid, prompting Diesel to come to his rescue. This occurrence led to the tag team being reunited, now known as "Two Dudes with Attitude". Diesel successfully defended the WWF title against Sycho Sid at the inaugural In Your Housepay-per-view in Syracuse, New York, and at the In Your House: The Lumberjacks in Denver, Colorado. AtSummerSlam 1995, Diesel retained the WWF title by defeating Mabel, who had won the 1995 King Of The Ring tournament. On September 24 at In Your House 3: Triple Header in Saginaw, Michigan, Diesel and Michaels challenged the reigning WWF Tag Team Champions Owen Hart and Yokozuna. The match had a winner-take-all stipulation, as in addition to the tag belts Diesel's WWF Championship and Michaels' recently won Intercontinental Championship were also on the line. When Hart did not show up at the event, he was replaced by Davey Boy Smith. In the course of the match, Hart arrived at ringside, entered the ring, and was pinned by Diesel for the win and the title, making him and Michaels holders of all three major WWF championships. The reign did not last long, however, as Hart and Yokozuna had the titles returned to them the next night due to Hart not being an official part of the match when pinned. Diesel's WWF Championship reign continued until November 19, when he was defeated by Bret Hart at the Survivor Series.Following the loss, Diesel began a heel turn by developing a rivalry against fan favorite the Undertaker by costing him a potential victory in his match against the WWF Champion Bret Hart at the Royal Rumble 1996. Diesel was the last wrestler eliminated in the Royal Rumble 1996 by Shawn Michaels, which eventually led to a rift between the two men. At In Your House 4: Rage In A Cage in Louisville, Kentucky Diesel lost his steel cage match against WWF Champion Bret Hart when he was attacked by the Undertaker.
Shortly before WrestleMania XII, both Diesel and Razor Ramon agreed to return to World Championship Wrestling as part of WCW PresidentEric Bischoff's drive to lure employees from the WWF to WCW with the offer of lucrative contracts. Diesel lost to The Undertaker at WrestleMania XII on March 31, then went on to feud with Shawn Michaels once again. In his last televised WWF appearance until 2002, Diesel challenged Michaels for the WWF Championship (which he had won from Hart at WrestleMania XII) at In Your House: Good Friends, Better Enemies on April 28. He wrestled Michaels for the title once again in a steel cage match at a house show on May 19, but was again defeated. After the match, Diesel, Michaels, Razor Ramon, and Hunter Hearst Helmsley, a group of off-screen friends known collectively as "The Kliq", hugged one another in the ring and wished each other farewell.This incident, later referred to as the "Curtain Call" or "MSG Incident", was a serious breach of character, as it showed heels and babyfaces consorting with one another. Shortly thereafter, Diesel and Ramon left the WWF and joined WCW.