On the April 5, 2004 episode of "Raw", Dinsmore made his World Wrestling Entertainment (WWE) debut as Eugene. He was portrayed as the "special" and overly excited nephew of Raw General Manager Eric Bischoff, who had savant-like wrestling ability from watching his favorites on television. Bischoff soon placed him under the care of the newly returned William Regal. Although Regal was originally dispirited at having to manage Eugene, he would grow fond of him and the two would quickly become firm friends. In May 2004, Eugene began a feud with Jonathan Coachman, who attempted to banish him from WWE (only to be stopped by The Rock). The feud culminated in Eugene's pay-per-view debut, when he defeated Coachman at Bad Blood. Eugene then feuded with Triple H, which led to match at SummerSlam, which Eugene lost. Two weeks later on "Raw", they fought a no disqualification match, which Eugene won after interference from Randy Orton. The next week, they had a steel cage match, which Eugene lost and suffered a kayfabe dislocated shoulder, ending the feud.