Sloane Stephens' title just the beginning of U.S. renaissance

NEW YORK -- Could there have been a better advertisement for the renaissance of U.S. tennis than the extraordinary tableau US Open champion Sloane Stephens and runner-up Madison Keys produced in the minutes following the match?

Among other things, those heartwarming moments were an apt comment on where U.S. tennis has recently been and -- better yet for U.S. fans -- where it is going.

No man or woman not named Williams had won a Grand Slam singles title in 14 years until Stephens beats Keys 6-3, 6-0 on Saturday evening. It's a tribute to how much the game has grown globally, and also to the lockdown imposed by Venus and Serena Williams.

The most alarming aspects of the drought for the U.S. were becoming more concerning after Serena left the game early this year and Venus turned 37 this summer. Venus, of course, made two major finals and the semis here, but the rains finally came in the form of Stephens, Keys and US Open semifinalist CoCo Vandeweghe.

That's just the tip of the iceberg. The really good news is that this trio never fully lived up to expectations -- until now -- to step up and represent the true face of the American game. Now that they have, it seems that visage is as striking as a yellow-happy-face emoji.

The U.S. currently has a stockpile of potential impact players of both genders testing the waters of the pro tour. They've lacked only time -- and the validation.

"Our pipeline is loaded," Martin Blackman, head of player development for the USTA, told ESPN.com. "And we attribute a lot of that to Venus and Serena. Maybe nobody else was breaking through during their time, but more importantly, they kept the bar calibrated to where it should be -- at the top of the game."

Among younger players, generations overlap but span roughly two to four years, thanks to the way junior tennis feeds the pro tours. That makes Vandeweghe, 26, Stephens, 24, and Keys, 22, the elder stateswomen of the American game. Blackman believes all three are now well on their way to becoming top-five impact players.

Right below that trio is another generation rapidly gaining experience on the pro tour in 18-and-under tour neophytes Kayla Day (ranked No. 128), Sofia Kennen (No. 139) and Claire Liu (No. 295). And let's not forget the highest-ranked 18-year-old in the WTA, No. 36 Catherine "CiCi" Bellis.

There's more:

While the PA announcer in Arthur Ashe Stadium was introducing the women's finalists with great pomp and ceremony, two young Floridians were already grinding on nearby courts, hoping to meet each other in the girls' 18-and-under final. Thirteen-year-old Cori Gauff, who has already announced in public that she wants to be "the greatest of all time," was playing in one junior girls semifinal on Court 6, fittingly close to the media entrance to Ashe. Over in the Grandstand, 16-year-old Amanda Anisimova was pounding away in the other. They both won and will meet here Sunday for the championship.

Gauff could be forgiven her brash remark; it had the ring of prophecy, not braggadocio. With so much talent at a young age, you half expect it to overflow out of her sneakers. She's a preternaturally mature competitor, as well.

Seven women appear in the ITF's top-25 juniors.

The situation on the men's side is different. There is no trio comparable to the three U.S. women who made the semis this week. Nor have the men done comparably well in this year's junior competition. But ...

"It may look like the women are doing better than the men," Blackman said. "But women tend to break through to become real good between the ages of 17 and 19, while men often make their move between 19 and 21."

Blackman also says that the U.S. has more 21-and-under men in the ATP top 300 than any other nation, as well as more 23-and-under men in the top 200. The big question, of course, is how many of those players will go on to become Grand Slam champions.

"Grand Slam champions are outliers by definition; they're special," said Colette Lewis, who run zootennis.com, a website that focuses on junior tennis. "But we Americans will certainly have contenders at majors. The group of boys two years ago [the generation of Frances Tiafoe and Taylor Fritz] is excellent, but the women have been three or four deep for a few years now."

Robert Lansdorp, the coach who developed countless pros, including Tracy Austin, Lindsay Davenport, Pete Sampras and Maria Sharapova, says that young men have time to develop their full potential -- but not as much time as some might think.

"I always thought you go on the tour three or four years, and that span gives you the basic area of where you're going to be for most of your career," Lansdorp told ESPN.com, citing the history of 20-year-old No. 6 Alexander Zverev. "After four years at No. 40, being No. 1 is just too big a reach. Usually, people who become No. 1 go up really fast; they don't stall or linger on the way."

That's a cautionary note for any young player, but it isn't a law of nature. Outliers are just that, and as the three women semifinalists at this US Open showed, breakthroughs can happen at the most unexpected of times.