Britain's Andy Murray demonstrated his grit and guile to frustrate Argentine 24th seed Francisco Cerundolo and start the 10th anniversary of his US Open victory with a first-round win.
Murray, 35, eventually edged a tight first set and then raced ahead in the second as Cerundolo became despondent.
The former world number one, who earned the first of his three major titles in New York, went on to win 7-5 6-3 6-3.
The Scot will play Australia's John Millman or American Emilio Nava next.
"It felt like five sets to me, it was tricky conditions, very humid and hot," said Murray.
"But I'm happy with the way I got through that one. He has had a brilliant year, I knew I had to play well and I did that in the important moments."
Murray is one of seven British players competing in the US Open singles and was the first through to the second round after opening play on Louis Armstrong Stadium, which is the second show-court at Flushing Meadows.
Former British number one Kyle Edmund is also playing on Monday as he continues his comeback from a serious knee injury, while 20-year-old Jack Draper - on his overseas major debut - and Harriet Dart will also look to join Murray in earning wins on day one.
Emma Raducanu starts her title defence on Tuesday, with seventh seed Cameron Norrie and Dan Evans also playing on day two.
More to follow.