2001: Hasim Rahman v Lennox Lewis: The 28year-old Rahman started as a massive 20-1 underdog but stunned Lewis with a sensational right hand knockout in the fifth round.
1996: Evander Holyfield v Mike Tyson: Holyfield, regarded as a shot fighter after retiring with a heart problem, was offered up as the next sacrificial lamb on Tyson's comeback following his release from prison but he confounded the pundits with a 10th round knockout of Tyson.
1990: James `Buster' Douglas v Mike Tyson: Douglas' 10th round knockout of the previously undefeated Tyson remains the biggest upset in the history of the heavyweight division.
1974: Muhammad Ali v George Foreman: The Rumble in the Jungle remains the most cherished upset of them all. Few gave Ali a prayer against Foreman, but, with Ali employing the famous `rope-a-dope' strategy, Foreman wore himself out before suffering an eighth-round knockout.
1964: Cassius Clay (Muhammad Ali) v Sonny Liston: Clay was a fresh-faced 22-year-old given no chance against the fearsome Liston, who had secured the title with a brutal knockout defeat of Floyd Patterson two years earlier. Clay proved too fast and too skilful for his older and slower opponent, ripping into the champion with lightning combinations.
