Spain competed at the 2004 Summer Olympics in Athens, Greece, from August 13 to 29, 2004. This nation has competed in every Summer Olympic Games since its official debut in 1920. Spain, however, boycotted two editions, the 1936 Summer Olympics in Nazi Germany, and the 1956 Summer Olympics in Melbourne when it joined the Dutch-led boycott, as a protest to the Soviet invasion of Hungary. The Spanish Olympic Committee sent the nation's third largest delegation in history to the Games. A total of 317 athletes, 177 men and 140 women, competed in 26 sports.
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The following is the list of number of competitors participating in the Games. Note that reserves for fencing, field hockey, football, and handball are not counted as athletes:
Two Spanish archers qualified each for the men's and women's individual archery.
Spanish athletes have so far achieved qualifying standards in the following athletics events (up to a maximum of 3 athletes in each event at the 'A' Standard, and 1 at the 'B' Standard).
Spain's men basketball team qualified for the event by reaching the final of the EuroBasket 2003.
<small>Qualification Legend: Q = Qualify to final; q = Qualify to semifinal</small>
Spanish divers qualified for three individual spots at the 2004 Olympic Games.
Spain qualified one fencer.
Spain qualified a men's and a women's team. Each team had 16 athletes with two reserves.
Ten Spanish judoka qualified for the following events.
Spanish rowers qualified the following boats:
<small>Qualification Legend: FA=Final A (medal); FB=Final B (non-medal); FC=Final C (non-medal); FD=Final D (non-medal); FE=Final E (non-medal); FF=Final F (non-medal); SA/B=Semifinals A/B; SC/D=Semifinals C/D; SE/F=Semifinals E/F; R=Repechage</small>
Spanish sailors have qualified one boat for each of the following events.
<small>M = Medal race; OCS = On course side of the starting line; DSQ = Disqualified; DNF = Did not finish; DNS= Did not start; RDG = Redress given</small>
Four Spanish shooters (two men and two women) qualified to compete in the following events:
Spanish swimmers achieved qualifying standards in the following events (up to a maximum of 2 swimmers in each event at the A-standard time, and 1 at the B-standard time):
Nine Spanish synchronized swimmers qualified a spot in the women's team.
Spain has qualified one table tennis player.
Four Spanish taekwondo jin qualified for the following events:
Ten Spanish tennis players (five men and five women) qualified for the following events:
Six Spanish triathletes qualified for the following events.
Two Spanish weightlifters qualified for the following events: