NEW YORK • Building the stamina to consistently survive the rigours of five-set matches will top the 33-year-old Andy Murray's agenda as the former US Open champion, who has undergone two hip operations, plots the revival of his career.

Playing his first Grand Slam singles match since the 2019 Australian Open, when there was talk of him retiring, the Scot produced an astonishing fightback from two sets down to defeat Japan's Yoshihito Nishioka in 4hr 39min in his opening round.

But that match seemed to take a toll on him as he bowed out against Canadian Felix Auger-Aliassime 6-2, 6-3, 6-4 on Thursday.

"The more tournaments that you play, the more matches that you play, you build up that sort of robustness in your body which right now I don't really have," said Murray, who won his first Grand Slam title at Flushing Meadows in 2012.

"So that's something that I'll need to build up over the next few months and hopefully beginning of next year. If I can stay healthy, I will be better able to back up difficult physical efforts."

He was unable to repeat his first-round heroics against the big-serving 21st-ranked Auger-Aliassime, who dominated from start to finish.

The Canadian smashed 24 aces and 52 winners in a one-sided affair. Murray mustered just two aces and nine winners.

"He's a big guy. He takes the ball on. There's obviously fairly quick conditions here, as well," said Murray. "Maybe served a little bit better tonight than he had in the last couple of weeks, which helped."

The Scot arrived for the US Open tune-up at the Western & Southern Open having not played a professional match since the Davis Cup Finals in November.

He picked up back-to-back wins over Frances Tiafoe and world No. 7 Alexander Zverev, but his level dropped against Milos Raonic in the round-of-16 loss.

"I felt like I played some good stuff at times, but it was quite up and down. I would like to play consistently better tennis," he said.​

"If you aren't playing at a high level consistently, then you will play longer matches because you're having dips."

With recent injury struggles, he also accepted it would be "extremely difficult" to add to his three Grand Slam titles.

But the 2013 and 2016 Wimbledon winner, who was renowned for his never-say-die attitude at the peak of his powers, insists he is not ready to throw in the towel yet.

"In terms of winning Grand Slams again, that's going to be extremely difficult to do. It was hard enough when I had two normal hips. So it will be difficult, but I'll keep trying," he said.

"Why not? Why shouldn't I try my hardest to do that? And if I don't, that's all right. But I might as well shoot for the stars.

"And if I don't - yeah, if I don't get there, then that's all right. But I'm trying my best to get the most out of what my body gives me now."

He added that he would also play in the rearranged French Open later this month.

REUTERS, AGENCE FRANCE-PRESSE

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