Andy Murray said he felt "crushed" as he contemplated the end of his Olympic journey after defeat in the quarter-finals of the men's doubles alongside Joe Salisbury in Tokyo.
The pair had high hopes of a medal after two strong performances and led Croatian duo Marin Cilic and Ivan Dodig by a set and a break with a point for 5-3 only to lose 4-6 7-6 (2) 10-7.
Both men looked devastated and, after allowing the dust to settle, Murray took to Twitter to express his disappointment and pride.
"I feel crushed after today's loss, sport can be brutal," said Murray. "Thanks so much @joesalisbury92 for the opportunity to play. You were brilliant. I wish it could have gone a little better but s*** happens.
"And if this is the end of my @olympics journey I want to say a huge thanks to @TeamGB and all the tennis support team for everything they have done to help me perform at my best over the years.
"It's been an absolute privilege to represent you and my country at four Olympics and it's given me some of the best memories of my life."
Murray is the only tennis player ever to win successive singles gold medals, and he also has a silver in the mixed doubles with Laura Robson from London.
Given his ongoing struggles to stay fit, which included pulling out of the singles here with a thigh strain, it seems highly unlikely he will compete at a fifth Games in Paris in three years' time.
"I don't know if I'll get the opportunity to play again," he said. "I had another chance with Joe to win a medal, we were so close, and that's what's disappointing. I would like to have done some stuff differently in the match to try to help out more."
Murray will now head home for more rest and recovery but is hopeful of being fit for the US Open, starting on August 30.
He said: "I'll see how the injury heals. That's what will dictate it. I'm not going to rush something if it's not there.
"My team think I should be OK to play the US Open judging by how I felt in matches here. It's not as physical as singles but there's a lot of explosive movements and my leg felt fine."
British interest in the tennis came to an end with a third-round loss for Liam Broady in the singles against Jeremy Chardy.
Broady, the last man into the field, had done brilliantly to make it through to the last 16, upsetting seventh seed Hubert Hurkacz on Tuesday, but Frenchman Chardy proved too strong.
It was another battling performance from 27-year-old Broady as he came from a break down to take the second set, but a 10-minute break before the decider because of the extreme heat refreshed Chardy and he ran out a 7-6 (3) 4-6 6-1 winner.
Broady said: "I'd be lying if I didn't say that I wanted to win today as well. As a tennis player and a competitor, that's all you want to do is to win every day so I'm obviously gutted about the way the match went.
"But I've got to maintain a little bit of perspective and when I go to bed tonight I think I'll be able to appreciate that a little bit more."
The Stockport player is having the best season of his career and will now look to push towards the top 100 having shown once again that he is capable of playing at a high level.
Broady, who is planning to head straight to Washington for qualifying at the ATP event over the weekend, said: "I had quite a successful junior career and a lot of the guys I competed with in juniors have done very well in the men's, so I've always had the belief that I can compete with these guys, but the tennis has maybe not been there to back me up.
"I need to keep working and keep doing what I'm doing and take this to the rest of the year and hopefully get my ranking to a place where I'm playing with these guys every week."
