Murray upbeat despite marathon defeat leaving GB well off the pace
Defeats for Andy Murray and Kyle Edmund have left Great Britain's Davis Cup title defence hanging by a thread in Glasgow.
Murray and Juan Martin del Potro took each other to the wire again but this time it was the Argentinian who came out on top.
A month after Murray battled for more than four hours to win Olympic gold in Rio, silver medallist Del Potro gained revenge with a 6-4 5-7 6-7 (5/7) 6-3 6-4 victory that lasted five hours and seven minutes.
That made it the longest match of Murray's career, surpassing the four hours and 54 minutes he took to beat Novak Djokovic in the US Open final in 2012 and Kei Nishikori in the Davis Cup first round in March.
Had Edmund defeated Guido Pella, Britain would still have been in a decent position, but he went down 6-7 (5/7) 6-4 6-3 6-2 to leave Argentina 2-0 up after day one and needing just one more point to secure a fourth final appearance in 10 years.
Murray tried to be upbeat but losing such a contest in the city of his birth, where he is a bona fide hero, will have hurt.
"I did great," said the world number two, who saved a set point in the third set with a sublime lob.
"I'm very proud of how I fought, I did fantastic. I fought for every point, tried as best as I could. That's all you can do.
"It was very fine margins. That happens in tennis and sport sometimes. It could have gone either way and he just played a little bit better in the fifth set."
The result ended Murray's 14-match winning run in the competition and meant he suffered a first singles loss at home.
It was also his second successive defeat from two sets to one up, a position from which he has been nigh on invincible in recent years, after last week's US Open exit to Kei Nishikori.
The common factor between the matches was fatigue, and Murray will wait to decide whether he plays in the doubles rubber today with his brother Jamie.
The problem for captain Leon Smith is that he left doubles back-up Dom Inglot out of the team and would have to turn to Dan Evans.
Murray said: "I'll have to see how I pull up tomorrow when I wake up and then probably make a decision.
"I've never played a match that long. I've played matches close to that length but none after an extremely long stretch of playing, so I don't know how I'll feel."
Away from the tennis court, it has also been a difficult week for Murray, who was forced to miss his grandfather's funeral to play on Friday.
"It's been hard but I always planned on playing," he said.
Del Potro's resurgence has been the feel-good story of the summer.
Out of the game for nearly two years and forced to undergo three wrist operations, Del Potro, 27, was close to retiring but instead has made himself a force once again.
The former US Open champion, who won a five-set match for the first time since 2010, said: "I'm so tired. I've got cramps everywhere. It was the longest match of my career and I won it against Andy playing here."
Del Potro's victory put the pressure on quarter-final hero Edmund to save the day.
The 21-year-old began well against Pella, ranked 49th to Edmund's 55th, and recovered from 3-0 behind to win the opening-set tie-break.
But from 3-2 up with a break in the third set, Edmund lost six games in a row, and, although he fought hard to stay in contention, it was not enough.