Christian Malcolm's bid to reach the Olympic 200m final has ended despite a strong semi-final performance.
The 33-year-old finished third in the third semi-final, which was won by Churandy Martina of the Netherlands.
Jamaica's Warren Weir was second while Malcolm's time of 20.51 seconds was not enough to secure a final spot as one of the fastest losers.
"I fancied my chances. I'm disappointed," said Malcolm.
"In my last Olympics games it would have been nice to make the final, but it wasn't to be."
Malcolm had qualified for Wednesday's semi-final after finishing second in his heat at the Olympic Stadium on Tuesday, in a time of 20.59 seconds.
Jamaica's 100m gold medallist Usain Bolt eased into Thursday's final in a time of 20.18 seconds along with compatriot Yohan Blake.
There was heartbreak for Sarah Thomas and Great Britain Women's hockey team, who lost 2-1 to Argentina in the semi-finals.
They will now will play for bronze against New Zealand on Friday at the Riverbank Arena.
"To know now that we're not going to get gold or silver is the worst feeling that I've ever had," Thomas said.
"We've got the bronze match on Friday and we've got to set our sights on that."
Earlier in the day, Hannah Mills guaranteed a medal in the 470 class at Weymouth by claiming second place in the penultimate race.
Mills and crew Saskia Clark are now tied for the lead with New Zealand ahead of Friday's medal race.
The Kiwi pair of Olivia Powrie and Jo Aleh suffered a disastrous race 10 on Wednesday in Weymouth, finishing in 18th while the British pair claimed second.
New Zealand will use that as their discard for the worst result, but means their 10th place in race five now counts towards their total.
Mills, from Dinas Powys in the Vale of Glamorgan, and Clark sit level with New Zealand on 33 points in the 470 class, with the Netherlands back in third on 52 points and France just in touch with 55.
With only the top 10 crews contesting the medal race, and points counting double, even if the Dutch won on Friday and GB finished last, Mills and Clark cannot be overtaken for second - barring a disqualification.
So the British pair should instead be able to concentrate on finishing ahead of New Zealand to claim another sailing gold for the hosts.