Steve Grotowski and John Garcia-Thompson's Olympic beach volleyball bid began with a defeat as the British pair went down in straight sets against Canada at a pulsating Horse Guards Parade.
A near-capacity crowd at the 15,000-seater arena did their best to cheer on the home favourites in their Pool F opener but their opponents just had that bit more guile around the court and emerged with a solid 21-19 21-13 win.
A huge roar welcomed the home pair at the start of the contest, which marked the first appearance by a British men's team in this sport at Olympic level.
Grotowski and Garcia-Thompson were far from overawed by the occasion, matching the Canadian pairing of Martin Reader and Joshua Binstock stride for stride in the early exchanges.
But daylight began to emerge when Canada went 17-15 ahead on a Binstock spike, and although GB got back to 19-19 on a great block by Grotowski, Canada just did enough to take the opener despite a magnificent defensive effort by the home team on set point.
A hugely fortunate touch off the net gave Canada an ace and a 4-1 lead early in the second set, and that lead extended to five points when Reader's dink shot just cleared the outstretched fingers of Grotowski.
A fluffed spike attempt by Garcia-Thompson saw GB fall 13-6 behind as the crowd began to sense a mood-deflating loss was imminent.
The British pair continued to fight hard despite seeing the gap extend to 10 points, but when needless mistakes began to creep in - Garcia-Thompson sent a serve harmless out of play late on - the writing was on the wall.
The home side saved one match point at 20-12 but Canada got the job done on the next point as Reader's deflected spike hit the sand to end Britain's resistance.