The greatest showman in tennis is set to begin his final run on the sport’s biggest stage.

Gael Monfils, 40, has announced that he will retire at the end of the 2026 campaign, meaning that Tuesday’s matchup against Adolfo Daniel Vallejo could be the Frenchman’s last appearance at the US Open.

Monfils is a +108 underdog against the Paraguayan on Tuesday evening, which happens to be Monfils’ 40th birthday.

US Open pick: Monfils vs. Vallejo odds, picks

Handicapping a match featuring Gael Monfils is always an adventure. In a sport based on routine and rhythm, La Monf is an outlier. He often seems more focused on entertaining than winning, sometimes to the detriment of the latter.

Monfils’ quixotic style of tennis is also very hard to prepare for. Against most opponents, you have a pretty good idea of what’s coming next. Against Monfils, you don’t. And there’s also the crowd factor.

Monfils may not be a household name in mainstream sports, but he is a beloved figure in tennis, and you can rest assured that Louis Armstrong Stadium will be packed to the gills on Tuesday night with fans who will be screaming their lungs out for La Monf.

This is a lot for a 22-year-old making his US Open debut to deal with.

Vallejo has begun to make inroads on the ATP thanks to a strong showing during the clay season, but he hasn’t put his best foot forward on hard courts just yet, and we don’t know how he will contend with the bright lights of New York City as he takes on one of the most popular figures in the sport.

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If this match were being played on the clay in Kitzbuhel, I could see how Vallejo would be priced as the favorite. But tennis is just as much a mental sport as it is physical, and all the intangibles on display in this contest favor the Frenchman.

Back Monfils to give the raucous New York a parting gift on Tuesday night.

The Play: Monfils +108 (FanDuel)

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Michael Leboff is a long-suffering Islanders fan, but a long-profiting sports bettor with 10 years of experience in the gambling industry. He loves using game theory to help punters win bracket pools, find long shots, and learn how to beat the market in mainstream and niche sports.