Knockout Kings 2001

Knockout Kings 2001 features a roster of 40 boxers, increased from the 25 featured in Knockout Kings 2000. Alongside retired boxers like Muhammad Ali and Sugar Ray Leonard, the game also featured contemporary boxers like Lennox Lewis and Shane Mosley. It is the only game in the series to feature female boxers, which included Mia St. John, Christy Martin, Lucia Rijker, and Regina Halmich.

Commentary during in-game matches was provided by Al Bernstein, Max Kellerman and Teddy Atlas, while Mills Lane and Richard Steele were featured as the referees. Jimmy Lennon Jr. was featured as the ring announcer. In the European version, the commentary was instead provided by Harry Carpenter, Barry McGuigan and Ian Darke.

The game received "favorable" reviews according to the review aggregation website Metacritic. John Gaudiosi of NextGen's January 2001 issue said that while the PlayStation version was "a good boxing game, it's still not as good as it could be. Also, if you played KK2000, you won't find much of a difference." Three issues later, Rob Smolka said of the PS2 version, "Honoring the strategy of boxing as much as the ferocity, this should enthrall fans of the sport." In Japan, where the latter console version was ported and published by Electronic Arts Victor on May 24, 2001, Famitsu gave it a score of 30 out of 40.

Air Hendrix of GamePro's December 2000 issue said of the PlayStation version, "The Knockout Kings series has lived up to its name as the PlayStation's boxing champ for a couple of years now, and this 2001 edition only continues that reign. With sharp new features, graphics, and controls, Knockout Kings 2001 owns the PlayStation boxing ring." Four issues later, he said, "If you're a boxing fan with a PS2, Knockout Kings won't move mountains for you, but it's still the PS2's best boxing game and [it] will provide plenty of thrills. If you've already conquered the PlayStation version, however, steer clear – this game is too similar to be worth its ticket price."