Kyle Edmund suffered a disappointing end to his US Open challenge after he was forced to retire from his third-round clash with Canadian teenager Denis Shapovalov.
The 22-year-old Brit had made a fine start at Flushing Meadows, claiming the first set 6-3 as he looked to continue his impressive run in New York.
Shapovalov, a qualifier on debut at this event, hit back by taking a hard-fought second set 6-3 as the match shaped up to be a thriller.
However, Edmund began to struggle with his neck midway through the third set, calling for the trainer while 3-2 up on serve.
From there, Edmund failed to take another game, eventually going down 3-6, 6-3, 6-3, 1-0 before retiring.
Shapovalov will now take on Spaniard Pablo Carreno-Busta in the fourth round, and is the youngest player to reach that stage since Michael Chang in 1989.
However, he was quick to offer his sympathies to Edmund after his retirement.
He said: “It is never good to win this way. I hope it is not too serious. Kyle has been playing great tennis and if he keeps it up, he will be doing really well.
“In one game, he hit a second serve and I heard him grunt like he had hurt something and he called the trainer. It is very unfortunate but I am happy to be in the fourth round.”