An entertainer at heart, Monfils pounded his chest with his right fist repeatedly and, after hugging opponent Diego Schwartzman at the net, used his right shoe to etch a sketch of a smiley face on the French Open main stadium's red clay.
Needless to say, his adoring public loved that, too.
Since 1983, when Yannick Noah became the most recent man from France to win the championship at Roland Garros, the locals have not had a whole lot to cheer about at their Grand Slam tennis tournament. So mark Wednesday as a rare bright light along the way: All five of the host country's men in action advanced to the third round, including three who were seeded — No. 12 Gilles Simon, No. 13 Monfils and No. 14 Jo-Wilfried Tsonga — and two who defeated seeded players — Nicolas Mahut and Benoit Paire.
"Everybody," Tsonga said, "remembers Yannick's victory."
Monfils trailed Argentina's Schwartzman two sets to one, before coming back and improving to 14-10 in five-setters with a 4-6, 6-4, 4-6, 6-2, 6-3 win filled with loud cheers between points and plenty of supportive cries of "Allez!"
"Actually, today I won because I had the crowd behind me," Monfils said. "They give me, let's say, some wings."
The five-foot-seven Schwartzman, who is nine inches shorter than Monfils, noticed the fans' effect, saying: "He always uses the people (to his advantage), in all his matches."
While some French players through the years have found the expectations of their countrymen too much to bear during these two weeks — Amelie Mauresmo comes to mind — Monfils and Tsonga occasionally thrive in the setting.
Both men have reached the semifinals in Paris — Monfils in 2008, and Tsonga in 2013. And both say they find the attention from the crowds more help than hindrance.
"For me," Tsonga said, "it's something positive."
What, he was asked, might the reaction in France be if someone could end its 32-year wait for a men's French Open title?
"First of all, I would be interested in winning! What would happen next? I don't really know. I have absolutely no idea. The fans are happy when we win a first-round match," a grinning Tsonga replied, enjoying his own one-liner, "so I guess winning the tournament would be something extraordinary for a country like ours."
Tsonga, the Australian Open runner-up in 2008, had little trouble Wednesday while defeating Israel's Dudi Sela 6-4, 6-1, 6-1. Simon also was a straight-set winner, 7-5, 6-2, 6-3 over Slovakia's Martin Klizan.
"If everything goes fine," Simon said, "I feel capable of doing great things."
He'll next face the 116th-ranked Mahut, best known for losing the longest match in tennis history to John Isner at Wimbledon in 2010. Mahut eliminated No. 24 Ernests Gulbis of Latvia, a French Open semifinalist last year, 6-3, 3-6, 7-5, 6-3. Paire, ranked 71st, beat No. 28 Fabio Fognini 6-1, 6-3, 7-5.
The only seeded Frenchwoman, No. 29 Alize Cornet, added to the general joie de vivre around the grounds — more crowded and louder than on other days of the week, because schoolchildren have half-days on Wednesday — by winning 6-2, 7-5 against Romania's Alexandra Dulgheru.
Cornet now plays Croatia's 33-year-old Mirjana Lucic-Baroni, who is ranked 70th and authored the biggest surprise of Day 4, compiling a 29-5 edge in winners to beat 2014 runner-up Simona Halep 7-5, 6-1.
Halep, seeded third, also lost to Lucic-Baroni at the U.S. Open last year. That tournament marked Lucic-Baroni's first trip to the fourth round at a Grand Slam event since 1999, when she was 17. Problems with financial backing and injuries contributed to years away from the tour.
"I take a lot of pride in what I went through in my life, the difficulties. And I know for a fact that a lot of people couldn't do it," Lucic-Baroni said. "I was stubborn. ... I believed in myself enough and I was strong enough to be here today."
Aware Cornet awaits, as does a crowd that can be expected to take sides, Lucic-Baroni said: "I wish at least three people will cheer for me in that match."
In Canadian results, the second-seeded team of Vancouver's Vasek Pospisil and American Jack Sock earned a 7-6 (3), 4-6, 7-6 (4) win over Victor Estrella Burgos of the Dominican Republic and Brazil's Joao Sousa. The 10th-seeded team of Toronto's Daniel Nestor and India's Leander Paes also advanced with a 6-2, 5-7, 7-5 win over the Australian team of James Duckworth and Chris Guccione.
Toronto's Adil Shamasdin and Australia's Rameez Junaid fell 6-4, 7-6 (5) to Jean-Julien Rojer of the Netherlands and Romania's Horia Tecau.
Follow AP Tennis Writer Howard Fendrich on Twitter at http://twitter.com/HowardFendrich