The future of men’s tennis has appeared to be previewing itself during the first week at the United States Open. Just how far into the future is anyone’s guess.
Teenagers and early twenty-somethings do not set the rules in this sport, as they once did. They do occasionally break them.
In the first four days of the tournament, Frances Tiafoe, a powerful 19-year-old American, pushed Roger Federer deep into a fifth set. Denis Shapovalov, an 18-year-old Canadian and perhaps the game’s most intriguing comer, displayed breathtaking southpaw strokes in stunning eighth-seeded Jo-Wilfried Tsonga. Andrey Rublev, a 19-year-old Russian who was not in the top 100 until June, wasted No.