After the 1971 playoffs, Chamberlain challenged heavyweight boxing legend Muhammad Ali to a fight. The 15-round bout would have taken place on July 26, 1971 in the Houston Astrodome. Chamberlain trained with Cus d'Amato, but later backed out, withdrawing the much-publicized challenge, by way of a contractual escape clause which predicated the Chamberlain-Ali match on Ali beating Joe Frazier in a fight scheduled for early 1971, which became Ali's first professional loss, enabling Chamberlain to legally withdraw from the bout. In a 1999 interview, Chamberlain stated that boxing trainer Cus D'Amato had twice before, in 1965 and 1967, approached the basketball star with the idea, and that he and Ali had each been offered $5 million for the bout. In 1965, Chamberlain had consulted his father, who had seen Ali fight, and finally said no. Lakers owner Jack Kent Cooke had also offered Chamberlain a record-setting contract on the condition that Chamberlain agree to give up what Cooke termed "this boxing foolishness." In 1967, recently retired NFL star Jim Brown acted as Chamberlain's manager, but Ali's manager Jabir Herbert Muhammad backed out of the Chamberlain-Ali match which was slated to take place at Madison Square Garden.