They all go. As has been said a thousand times in tennis, the lone match no one will win comes when they are standing across the net from Father Time.

In a recent article for The Ringer, writer Tumaini Carayol ponders the question of the past five years, still ongoing: "What happens when the legends finally retire?" This is the question that players and coaches, tournament heads and TV programmers, casual fans and die-hards alike are grappling with.

The piece poses questions and offers up data points about how the ATP and WTA tours, respectively, have known feast and relative famine. They've floated and fallen.

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At the end of it, that's the ebb and flow of business.

"Federer, Nadal, and Serena remain the few players capable of piercing that patriotic lens and generating clicks and interest for audiences around the world."

Plainly said: Roger Federer, Rafael Nadal, Serena Williams, and Novak Djokovic move units.

As many have opined in the past couple years, there's an expected late-2020 drain in both ATP and WTA talent. Federer, Serena and Venus Williams, Bob and Mike Bryan, Maria Sharapova, and others have been projected as potential retirees at that time, after the Olympic Games in Tokyo and the US Open in New York.

But new stars shimmer in the figurative sky. As the writer Carayol notes, Naomi Osaka, Coco Gauff, and Bianca Andreescu have signed on for major roles in the WTA conversation for years—if not decades—to come.

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It may be that the ATP finds its own footing, with young guns rising up. From Grigor Dimitrov to Alexander Zverev, the preceding generation (or one-point-five generations) might be passed by the likes of Felix Auger Aliassime and others to come. Each generation bends to the next.

Time will tell. Trust: Tennis will be well.