The 38-year-old wound back the clock as he caused one of the biggest upsets of the year's first grand slam, knocking off fourth seed Taylor Fritz 3-6 7-5 7-6 (7-1) 6-4 on Saturday.
It extended Monfils' winning run to eight matches after he became the oldest man to win a tournament since at least 1990 with his Auckland Classic triumph this month.
The charismatic entertainer produced 58 winners to Fritz's 44, doubled his opponent's tally of aces (24-12) and dropped just one service game.
Gael Monfils had all the answers against Taylor Fritz. (James Ross/AAP PHOTOS)
He sealed the surprise result with an ace down the T and celebrated in style with a few moves better suited to the dance floor.
"I want to be myself ... I just done what was in my mind, so that was my way to express my joy," Monfils said.
The upset was Monfils' first win over a top-five opponent at a grand slam since 2008, when he beat David Ferrer in a French Open quarter-final.
He joined retired great Roger Federer as the only men to reach the fourth round at Melbourne Park aged 38 or older.
But the two-time Australian Open quarter-finalist - also semi-finalist at Wimbledon and the US Open - won't let his mind wander towards the possibility of a first major title after more than two decades on tour.
Instead, he'll spend part of Sunday in an ice bath recovering for a fourth-round match-up with Ben Shelton.
"Win? No, you know, to be honest with you, it is not even a dream to win the tournament," Monfils told reporters.
"My dream is to be old and with a lot of kids and healthy.
"That's your dream, I guess, to win a slam. I tell you my dream. My dream is to have an unbelievable family.
"Tennis is cool. Of course, you know, you want to have goal, dream, whatever. But my dream is out there."
Conceding Monfils simply outplayed him, Fritz, who was runner-up to Jannik Sinner at the US Open last September, had no doubt the Frenchman could do some damage in the second week in Melbourne.
Taylor Fritz serves against Gael Monfils. (James Ross/AAP PHOTOS)
"If he can continue to play like how he played today for five sets, I think he's going to be tough for anybody to beat," Fritz said.
"He's returning all my serves, even when I'm hitting really good serves.
"The way he's serving on top of that, plus how big he's serving his second serve, it's just really tough to play."
Monfils next faces a man 16 years his junior in 21st seed Shelton, 22.
The talented young American outlasted 16th seed Lorenzo Musetti, claiming a 6-3 3-6 6-4 7-6 (7-5) win over the Italian on John Cain Arena.
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