Andy Murray has admitted he is feeling "off the pace" for his return to the ATP Tour this weekend.
The two-time Wimbledon champion will face American wild card Frances Tiafoe in the opening round of the Western & Southern Open at Flushing Meadows.
The tournament is a warm-up for the US Open at the same venue from 31 August.
"I'm looking forward to it, just to be back competing again," said Murray, whose last ATP event was November's Antwerp Open.
The Scot has struggled with injury since then and, although he is now back to full fitness, he admits to some rustiness.
"I've really enjoyed the last few days just practising with top players, which I've kind of done a little bit back home but not that much," he added.
"It's very different conditions, very lively, quick, very hot. I've been practising with [Dominic] Thiem, [Andrey] Rublev and [Karen] Khachanov. Those guys don't really hold back.
"It's a bit of a different speed to what I've been used to. I felt a little bit off the pace at times but I'm feeling quite good on the court physically in terms of my hip.
"That was really all I wanted. I wanted to get to the US Open feeling pretty pain-free so that I could enjoy playing in a grand slam again.
"The last few years, they've been tough. I felt like I was doing really well at the end of last year - I was so excited for the beginning of this year.
"I had the setback again in November and a tough few months after that - I didn't really know exactly what was going on with the hip.
"Now I'm in a position to compete again and hopefully play in a major."
Murray, who said he will manage his schedule to avoid further setbacks, travelled to New York 10 days ago and has entered the tournament's bio-secure bubble, staying in a hotel on Long Island.
"Since I got in, I've been tested [for coronavirus] twice," Murray said. "From what I've seen so far, everyone seems to be doing the right things."
Murray is one of five Britons in the main draw with Dan Evans facing a tough opener against Russian 10th seed Andrey Rublev while Kyle Edmund plays former Wimbledon and US Open finalist Kevin Anderson with the South African on the way back from elbow and knee surgery
In the women's draw, eighth seed Johanna Konta has a bye in the opening round while Heather Watson faces American Bernarda Pera.