Britain's men, back in the Olympics for the first time in 52 years, suffered the agony that England have virtually perfected in World Cups and European Championships when they were beaten 5-4 on penalties by South Korea at Cardiff's Millennium Stadium.
At stake was a semi-final against Brazil and a chance of at least adding a bronze to the medal haul that Britain continued to collect earlier on Saturday with three athletics golds and three elsewhere.
Instead, Britain's flirtation with Olympic football is now probably over for many years.
With the game level at 1-1 after extra time and the teams locked at 4-4 in the shootout, Daniel Sturridge's stop-start run-up ended with Korea's substitute goalkeeper Lee Bum-young saving his shot.
Ki Sung-yueng, who plays for Celtic in Scotland, converted his penalty to give the Koreans a 5-4 victory and send Britain out with a somewhat ironic twist of the knife.
The Scottish Football Association, along the FA of Wales and the Northern Ireland FA, have long opposed the notion of a British team because they fear it will compromise their independent status within football's governing body FIFA.
Along with dominant England, who supported having the British team, the four compete as separate nations in non-Olympic football.
The reticence of the three means a British side have largely stayed out of the Games since Rome 1960 with their last Olympic involvement a failed qualifying campaign for Munich 1972.
UNLIKELY AGAIN
Coach Stuart Pearce, who did well with a squad that came together only four weeks ago, does not think it likely they will take part in the qualifiers for the 2016 Olympics in Rio de Janeiro.
"The format of Team GB in the Olympics would be fantastic but I do not think it will happen again," Pearce told reporters.
"Home advantage has allowed us to have this opportunity but when you look at international programmes and bringing nationalities together, where are we going to find the time to enter a qualification period?"
Pearce's 18-man squad comprised 13 Englishmen and five Welsh players, including Ryan Giggs, one of three over-age players in the age-restricted squad which also included another Welsh veteran Craig Bellamy - the outstanding player in their four-match campaign.
Giggs created a slice of Olympic history against the United Arab Emirates at Wembley last Sunday when, at the age of 38 years and 243 days, he became the oldest man to play in and then score in the Games football tournament.
He added another six days to that playing record when he came on as a late substitute against South Korea in his birth city of Cardiff, but even though he netted a superb penalty in the shootout the midfielder could not steer his team through.
Britain improved after their first official game - a 2-0 defeat by Brazil in a warm-up at Middlesbrough on July 20 - drawing with Senegal and then beating the UAE and Uruguay to win their group.
They might have beaten
