What past Next Gen stars used to look like

In the sport's history, there have been a lot of Alexander Zverev types—meaning young players who broke through as teens and made early debuts at year-end championships. Just imagine if there had been a Next Gen ATP Finals event for 21-and-under stars before this season. It would have been stocked full of future champions in decades like the '70s and '80s.

Here are the teenagers from the past that went on to play with the best of the best:

1

Bjorn Borg, 1974

Over the summer, the 18-year-old from Sweden won his first French Open title, making him the youngest-ever male victor. He earned a place in the season-ending event on grass in Melbourne, and went 1-2 in the round-robin stage. Borg would later win the tournament in consecutive years, in 1979 and 1980.

2

John McEnroe, 1978

The year-end championship for the 1978 season was held in January 1979 in Madison Square Garden. Playing in front of his home crowd, the native New Yorker’s debut at the tournament was a successful one as he beat Arthur Ashe in the final, a month shy of turning 20.

3

Jimmy Arias, 1983

Another young American with a game the complete opposite of McEnroe’s, a 19-year-old Arias qualified for the year-end event in Madison Square Garden on the strength of his forehand and four titles won that year, including the Italian Open.

4

Aaron Krickstein, 1984

Arias’ run to the Masters was replicated by another Nick Bollettieri protégé the following year. Krickstein, who, after becoming the youngest player to ever win a tour title in 1983, made it to the year-end tournament in 1984 as a 17-year-old.

5

Boris Becker, 1985

With his blistering serve and athletic game, Becker won Wimbledon earlier in the year. At his first appearance in the year-end championship, the 18-year-old German reached the final. He’d go on to win the title three times.

6

Stefan Edberg, 1985

Defying the conventional Swedish style of play emulated by Borg and Wilander, Edberg—one of the greatest serve and volleyers of all time—lost in the first round as a 19-year-old. Four years later, he’d win the title, defeating his main rival Becker in the final.

7

Andre Agassi, 1988

With six titles, a No. 3 ranking and two Grand Slam semifinals, Agassi entered his first year-end appearance as a contender. However, the 18-year-old went 1-2 in his round-robin group. A year later, he’d also struggle, but in 1990, he won it all for the first big title of his career.

8

Pete Sampras, 1990

The surprise US Open champion in 1990, Sampras only won one match at his first year-end ATP World Tour Championships, the first time the tournament was held in Frankfurt, Germany. He’d make up for that ignominious debut, going 5-0 in future finals.

9

Michael Chang, 1989

Precociousness was the defining trait of the American, who, earlier in the year, became the youngest male to ever win a Grand Slam title at just 17. He failed to win a match at the year-end tournament that year, but would reach the final in 1995, another significant achievement on his way to the Hall of Fame.

10

Mats Wilander, 1982

The next great Swede after Edberg to climb up the ranks, the 18-year-old French Open champion was seeded fifth at that year’s final tournament. He lost in the first round to Jose Luis Clerc of Argentina.

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