He is currently without any coach at all, in an era when some players have two.
What Monfils has never done, despite all his talent and in some cases, because he has appeared to value style over substance right there on court, in the middle of a point, preferring the spectacular to the sufficient is reach a Grand Slam final. He took a step closer Tuesday at the U.S. Open during a surprisingly matter-of-fact 7-5, 7-6 (6), 7-5 victory in the fourth round over No. 7-seeded Grigor Dimitrov, a man considered one of the sport's up-and-comers.
There is a narrative building around the 20th-seeded Monfils' success so far this year at Flushing Meadows, where he hasn't dropped a set en route to reaching the quarterfinals for the first time since 2010: He has matured, is playing more carefully, more seriously.
The Frenchman, who will face Roger Federer for a spot in the semifinals, rejected that notion after Tuesday's win.
"I'm the same. So I will say I'm a bit more lucky than I was maybe sometime in the past. I think I haven't changed a lot, to be honest. I haven't changed a lot," Monfils said. "I just play maybe solid today, but I'm still the same."
Federer advanced to the U.S. Open quarterfinals for the 10th time in 11 years by eliminating 17th-seeded Roberto Bautista Agut 6-4, 6-3, 6-2 Tuesday night. Federer won the point on 35 of 52 trips to the net.
The other quarterfinal matchup on that half of the draw will be No. 6 Tomas Berdych against No. 14 Marin Cilic. Berdych beat 20-year-old Dominic Thiem 6-1, 6-2, 6-4; Cilic was a 5-7, 7-6 (3), 6-4, 3-6, 6-3 winner against No. 26 Gilles Simon, who was treated for a back problem early on.
In women's quarterfinals Tuesday, 39th-ranked Peng Shuai of China ended the precocious run of 17-year-old Belinda Belic of Switzerland 6-2, 6-1. Peng's next opponent will be No. 10 Caroline Wozniacki, the 2009 U.S. Open runner-up, who overwhelmed No. 13 Sara Errani 6-0, 6-1 in a wind-whipped match Tuesday night.
U.S. Open highlights
O Gael Monfils of France wins in straight sets to advance to the quarterfinals, where he'll face Roger Federer.
• China's Peng Shuai beats Swizterland's Belinda Belic, 17, in Tuesday's quarterfinals.
O Wednesday's quarterfinals
10 a.m. and 4 p.m., ESPN