Andy Murray is expecting another difficult match after coming from two sets down to beat France's Adrian Mannarino in the second round of the US Open in New York late last night.
Murray will face Brazilian Thomaz Bellucci, the 30th-seed, in the next round.
"It will be a tough match. He's playing very well and is close to his career-high ranking," Murray said.
"He beat James Ward and it will be very tricky."
Murray looked to be heading for an early exit after going two sets down to Mannarino.
"It was an extremely tough match," he said.
"He hits the ball very flat, has fantastic timing, and it is difficult to read where he is going to hit the ball.
"Thankfully in the third set I managed to grab the break point after missing chances in the first two sets. Like I said, it was very tough."
The Scot came from two sets down in sweltering heat to beat Mannarino and reach the US Open third round.
In temperatures pushing 33 degrees Celsius in New York, Murray failed to find his best form until it mattered most as the world number three came roaring back to win 5-7 4-6 6-1 6-3 6-1.
It is Murray's 30th consecutive grand slam in which he has made round three and he will now play Bellucci for a place in the last 16.
Britain's Johanna Konta pulled off the biggest win of her career as she knocked out ninth seed Garbine Muguruza to reach the third round.
Muguruza has made the French Open quarter-finals and the final at Wimbledon this year but could not find an answer to Konta, who sealed a shock 7-6 (7/4) 6-7 (4/7) 6-2 victory.
Konta had only managed one grand slam win prior to this tournament but she now has two in three days and goes through to face Germany's Andrea Petkovic in round three.
Konta said: "I'm just so tired. She probably didn't play her best but she's an incredible fighter and no matter what level she brings to the court she always brings her top 10 mentality.
"I had to fight for every point and I'm just really happy to come back another day."