Novak Djokovic and Casper Ruud were made to work hard for victory in their opening matches at the Paris Masters on Tuesday.
For Djokovic, a 10th win in a row came in an absorbing battle with his Paris-born American opponent Maxime Cressy, who displayed a typically aggressive approach on serve, with 15 aces and 10 double faults overall.
Djokovic was strong on his own delivery, however, with the Serbian losing just six points on serve and not facing a break point on his way to a 7-6 (7-1) 6-4 victory.
"I'm happy with the way I played," Djokovic said. "When chances were presented, I was able to use them, even though I did have some missed break points.
"But it was very challenging, first match with a guy who serves extremely well and strong and fast.
"He's comfortable coming to the net. It's nice to see. I think he's the only guy that really comes to the net after every first and second serve. I think it's good for tennis to see that, particularly in these modern times when most of the players are playing from back of the court. He's a very athletic guy.
"It's difficult to play him definitely in these kind of conditions where balls are flying through the court and it's quicker than it was last year. So tough to break.
"But I didn't make too many unforced errors. I'm very pleased with the way I served, with the way I was holding my service games. Just the way I felt, the way I played, it was all positive."
Third seed Ruud ground out a 6-1 7-6 (9-7) victory against Frenchman Richard Gasquet, with the Norwegian saving three of four break points in what proved to be a tightly fought contest.
Mistakes from Gasquet were ultimately costly, the veteran having 10 unforced errors in the second set compared to Ruud's two.
Seventh seed Andrey Rublev was also victorious, the Russian winning 6-2 6-3 against American John Isner, while the British duo of Jack Draper and Dan Evans progressed to the last-32 stage, beating Arthur Rinderknech and Brandon Nakashima respectively.