|US Open 2021|
|Venue: Flushing Meadows, New York Date: 30 August-12 September|
|Coverage: Daily radio commentaries on BBC Radio 5 Live Sports Extra/BBC Sport website and app, with selected live text commentaries and match reports on the website and app|
Andy Murray produced his finest display in four injury-disrupted years but fell agonisingly short of beating Greek world number three Stefanos Tsitsipas in a thrilling start to the US Open.
The British former world number one played in a manner reminiscent of his best as he led by two sets to one.
But Tsitsipas fought back to win 2-6 7-6 (9-7) 3-6 6-3 6-4 in New York.
Dan Evans is the only Briton through after defeats for Heather Watson, Harriet Dart and Cameron Norrie.
Johanna Konta withdrew from her first-round match because of a thigh injury, meaning teenager Emma Raducanu and Katie Boulter - who play on Tuesday - are the nation's last remaining hopes in the women's singles.
Murray, like so often in the past, was the British player who stole most of the attention on the opening day of the final Grand Slam of the 2021 season - even in defeat.
Now ranked 112th in the world, the Scot was aiming for his biggest win by ranking since his career was derailed by a serious hip injury that left him facing retirement.
Fired up throughout and relishing the magnitude of the occasion, 34-year-old Murray moved freely and hurt Tsitsipas with his quality from all over the court.
A seismic shock beckoned before 23-year-old Tsitsipas - one of the favourites for the title - maintained his focus and bided his time to win in four hours 49 minutes.
"It did not come easy to turn the match around. I had to make a lot of sacrifices," Tsitsipas said.
After being irritated by Tsitsipas' eight-minute bathroom break before the deciding set, Murray exchanged a terse handshake with his opponent before continuing to loudly chunter "it's a joke" while he gathered his belongings.
Even the affectionate and rousing reception which accompanied the 2012 champion off the court could not hide his annoyance.
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Defying the odds is something Murray has managed to do on several occasions in recent years, but beating an opponent of Tsitsipas' standing over five sets at a Grand Slam would have been a new benchmark.
Niggling injuries since major hip surgery have continued to hamper his progress and, having played only 12 matches this year before the US Open, doubts remained about his chances of ever competing again with the world's best.
While Murray arrived in New York speaking positively about his physical state, he said it was his game that needed to be "in a better place".
Against Tsitsipas, it certainly was. And at a level where it has rarely been - if at all - since Murray first developed the hip problem at the 2017 French Open.
Playing with freedom of movement and plenty of power, Murray's quality drew numerous errors from Tsitsipas as he dominated the opening set and threatened to take a two-set lead.
A deft lob from Murray - a trademark backhand flick reminiscent of the one with which he clinched victory for Britain in the 2015 Davis Cup final - put him 5-3 ahead in the second-set tie-break, before a slip on a patch of his own sweat may have bizarrely prevented him from going two sets in front.
Soaked from head to toe in the humid conditions, Murray became irritated by his sodden footwear and, after seeing two set points slip away, produced a double fault that helped Tsitsipas level.
Strangely, Murray did not have another pair of trainers with him - meaning he even tried to dry his drenched ones with the air conditioning unit next to his chair.
Murray's level dropped at the start of the fourth as Tsitsipas raced 5-0 ahead before ensuring the match would go into a decider.
More drama came when Tsitsipas spent almost eight minutes off the court before the fifth set, leaving Murray furious and immediately a break down - from which he could not recover.
"It's never taken me that long to go to the bathroom ever," Murray said to US Open match supervisor Gerry Armstrong.
Evans through in 'brutal' conditions
Evans, seeded 24th, appeared to struggle physically before winning 6-3 6-7 (6-8) 6-4 6-1 against Brazil's Thiago Monteiro.
After missing the Olympics because he contracted Covid-19, 31-year-old Evans had lost four of his five matches since Wimbledon and looked to be waning as Monteiro levelled at one set all.
Evans needed ice packs during the second set and had treatment on a foot after winning the third, but raced to 4-0 up in the fourth set before completing victory.
Former British number one Tim Henman, working as a television commentator, described playing in the heat and humidity as "brutal".
Evans will play American world number 64 Marcos Giron in the second round.
Watson, Dart and Norrie go out
Watson, 29, was beaten 6-1 6-4 by Slovenia's Kaja Juvan, while qualifier Dart lost 6-7 (6-8) 6-4 6-2 to France's former world number four Caroline Garcia.
Watson, set to become Britain's top-ranked women's player following Konta's withdrawal, has now lost all 10 of her first-round matches in New York.
Dart, 25, played excellently in the first set but trailed by a break in the second when she had to go off court for lengthy treatment on what appeared to be a left leg injury.
Norrie, the 26th seed, had reached the third round in the past four Grand Slams, but was beaten 6-4 6-4 6-3 by highly rated Spanish 18-year-old Carlos Alcaraz, the youngest player in the men's top 100.
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