Michael Spinks turned professional with a win over Eddie Benson, knocked out in one round on April 17, 1977 in Las Vegas. With that, Spinks began a 31 fight winning streak that would almost extend to the end of his career. After four more wins, Spinks finished '77 with the first fight that began a gradual ascent in opposition quality: an eight-round decision over Gary Summerhays, a popular young boxer of the time. In 1978, Spinks won two fights, including an eight-round decision over former world Middleweight title challenger Tom Bethea, in the same undercard where his brother Leon dethroned Ali as
Mike Tyson vs. Michael Spinks between Tyson and Spinks grew to settle the issue of who the real champion was, but negotiations were protracted because Tyson's co-managers Bill Cayton and Jimmy Jacobs and Spinks' manager Butch Lewis struggled to agree on terms. Negotiations temporarily broke down when Lewis insisted on a $15 million guarantee for his fighter. Annoyed at constantly being asked about the fight, Tyson eventually demanded that his managers reach an agreement with Lewis. By April an agreement had been reached, although another problem arose when the IBF threatened to strip Tyson of their title if the fight was not scheduled for 15