Gael Monfils is pleased with his form but insists he is still getting better after reaching the US Open semifinal.

The 10th seed overcame Lucas Pouille 6-4, 6-3, 6-3 in an all-French quarterfinal at Flushing Meadows on Tuesday.

It marks just the second time Monfils has reached the last four at a grand slam, and first since the 2008 French Open.

Ahead of facing either Novak Djokovic or Jo-Wilfried Tsonga, Monfils said his run in New York was satisfying.

"I'm happy with my performance. I think it is never easy to play a quarterfinal against a French guy, you know," he said.

"I think I handled it pretty good mentally and tennistically. I'm happy with that and where my game is. I see new or good stuff today. Serve was a bit better.

"I have been saying I think to the French press that I could serve faster. I think I did it great today. Still moving good. I'm very happy."

It also ended a dream run for Pouille, who eliminated Rafael Nadal in thrilling fashion in the fourth round.

Pouille, 22, said his difficult passage to the last eight, which included three five-setters, took its toll.

"Of course I was a bit tired today. I played four matches, one in four sets, and then all three in five," he said.

"So, yeah, it would have been better if I played a bit less time on court. It's OK. I did my best today.

"Gael was playing very good. He's physically very fit. He's moving so well. And I think, as I said after Nadal's match, he's in very good form. Yeah, I think he was better than me today."