|Venue: Flushing Meadows, New York; Dates: 31 August-13 September|
|Coverage: Live radio and text commentary on every Andy Murray match plus selected others.|
Britain's Andy Murray fought back from two sets down to beat Frenchman Adrian Mannarino and keep his US Open hopes intact.
The third seed was in serious trouble before recovering to win 5-7 4-6 6-1 6-3 6-1 in stifling conditions at Flushing Meadows.
Murray goes on to face Brazilian 30th seed Thomaz Bellucci in the third round on Saturday.
British number two Aljaz Bedene lost 3-6 6-4 6-4 6-2 to American Donald Young.
In the women's draw, Briton Jo Konta enjoyed a stunning three-set win over ninth seed Garbine Muguruza that lasted three hours and 23 minutes.
|Murray by numbers|
|Murray has now won eight times from two sets down during his career||This was the first time he has come back to win from two sets down since Wimbledon 2013 against Fernando Verdasco|
|Murray has spent exactly six hours on court over two rounds||He played 282 points, hit 39 aces, 91 winners and 58 unforced errors|
Feeling the heat in New York
Murray had not lost in the first week of a Grand Slam since 2010, but he flirted with that outcome against world number 35 Mannarino.
With the temperature around 32C and humidity at 50%, Murray looked like the most uncomfortable person in Arthur Ashe Stadium for much of the afternoon.
"It was an extremely tough match," a sweat-drenched Murray said afterwards.
For the best part of two hours he struggled to find any rhythm, took one pile-driver from Mannarino between the shoulder blades, wrapped an ice towel around his neck at the changeovers and castigated his team in the stands.
Failure to convert six of seven break points in the first set, including from 0-40 at 5-6 down, only added to his frustration.
Mannarino, in contrast, looked calm and increasingly capable of pulling off only the second top-10 win of his career to create a huge shock.
"I just had to kind of tell myself that I would get there eventually," said Murray. "I managed to turn it round."
'He has such an unorthodox game'
A flat performance was in danger of becoming Murray's last at a Grand Slam in 2015 when he lost 11 straight points to fall two sets down.
However, a break at the start of the third jolted him into life, the Scot fist-pumping as his support team, including mum Judy, got to their feet.
The 2012 champion was in control from then on, taking the set as his will to win and supreme fitness overcame a nagging lack of consistency in his game.
One point of astonishing scrambling by Murray at the start of the fourth brought the crowd to their feet, urged on by the Briton, and he would break for a 2-1 lead.
The turnaround was effectively complete when Murray won 11 of 12 points in the decider to take a 3-0 lead, and he closed it out after a punishing three hours and 17 minutes.
"I thought he played some really, really good tennis," said Murray.
"He has such an unorthodox game, I didn't really feel that comfortable at many points out there in the match.
"But I was happy - very happy - with the way I fought through that and finished the match stronger than him."
|BBC Sport tennis correspondent Russell Fuller:|
|"Mannarino predicted before the match that it was going to be very complicated, but he didn't mean for Murray. The world number three's powers of recovery are renowned, but this one seemed far from certain after two sets.|
|"Murray seemed listless and out of sorts until he once again managed to rediscover that spark, and brush Mannarino aside without further fuss. He has, though, already spent six hours on court, Novak Djokovic just two hours and 40 minutes."|
Bedene falls short of Slam best
Slovenia-born Bedene's wait to reach the third round of a Grand Slam continues after Young fought back from losing the first set in front of his home crowd.
The 26-year-old world number 57, who switched allegiance to Britain in March, is ranked 11 places higher than Young and looked to be in control when he led 2-0 in the second set.
But Young, 26, instantly broke back as Bedene lost his rhythm to eventually succumb in two hours and 42 minutes.