After three years of inactivity, Ali returned to the sport, leading to his first epic clash with Joe Frazier in 1971, ushering in a "golden age" of heavyweight boxing. Ali, Frazier, and the heavy-hitting George Foreman were the top fighters in a division overloaded with talent. Among the middleweights, Argentine Carlos Monzón emerged as a dominant champion, reigning from 1970 to his retirement in 1977, after an unprecedented 14 title defenses. Roberto Durán dismantled opponents for 6½ years as lightweight champion, Defending the title 12 times, 11 by knockout.