National Championship – competition is annulled by the DFB following a protest by Karlsruher FV that matches have not been played on neutral grounds as stipulated by the rules.
Portugal
Benfica founded in Lisbon as the Grupo Sport Lisboa. In 1908, it merges with SC de Benfica to form Sport Lisboa e Benfica (SL Benfica).
29 April — Barbados Joe Walcott meets Dixie Kid to defend the World Welterweight Championship and, though well on top, is disqualified by the referee after 20 rounds for an alleged foul. Kid claims the title but it is subsequently discovered that the referee has bet on Kid to win and so Kid's claim is widely disregarded.
31 October — Joe Gans meets Jimmy Britt in San Francisco to defend the World Lightweight Championship. Britt knocks Gans down four times but, after the last one in the fifth round, he hits Gans again before he has stood up and is disqualified for the foul. Afterwards, Gans vacates the title which is awarded to Britt. Two years later, Gans will claim that the fight has been fixed by his and Britt's managers.
31 December — during a New Year celebration, Walcott accidentally shoots himself in the hand to effectively ending his days as a top prizefighter. While he will return to the ring in 1906 (losing his welterweight title in the process), he never regains his old form and loses most of his subsequent fights.
2 March — Ottawa plays Montreal Wanderers to a 5–5 tie in a Cup challenge, but Montreal refuses terms of continuation of series and defaults.
March — Quebec Bulldogs win the CAHL championship and demand the Stanley Cup, but the trustees rule the Cup stays with Ottawa. Quebec refuses to play Ottawa in a challenge.
March — Ottawa defeats the Brandon Wheat Kings 2 games to 0 in a Cup challenge.
18 December — Dawson City Nuggets begin a 4,000 mile journey by dog sled to play the Ottawa Hockey Club in a Stanley Cup challenge scheduled for 13 January 1905.
The third Circuit des Ardennes is run on 25 July over 591.255km (118.251km x 5 laps) in the vicinity of Bastogne. The winner is George Heath (USA) driving a Panhard-Levassor 70hp in a time of 5:30:49.
Vanderbilt Cup
William Kissam Vanderbilt II launches the Vanderbilt Cup at a course set out in Nassau County, New York on Long Island. It creates controversy in New York with numerous attempts made, including legal action, to try to prevent it taking place. The inaugural race is run over a 30.24 miles (48.7km) course of winding dirt roads through Nassau County. Several European drivers with experience of the Gordon Bennett Cup take part and the event is a huge commercial success. The winner is George Heath (USA) driving a Panhard-Levassor 70hp.