Top 20 Under 20: Where are they now?

Just over five years ago, I made my first of a series of posts called "Top 20 Under 20" where I rated the 20 most promising teenagers on the ATP. Now seems like a good time to reflect on these rankings and see what I got right and what I got wrong.

I will comment on the 20 players in the original order that I ranked them on July 17, 2014.

1. Nick Kyrgios - I put Kyrgios at No. 1 since this ranking came out shortly after he had defeated No. 1 Rafael Nadal to reach the Wimbledon quarterfinals. At the time, he was the only teenager in the top 100. Since then Kyrgios has only reached one other grand slam quarterfinal and he has failed to do so in the last 16 majors that he has played in. There are now eight players ranked ahead of Kyrgios that are younger than him. He has had flashes of brilliance over the last five years, but his career has been a disappointment with his tantrums being the most defining aspect of his career so far.

2. Alexander Zverev - Zverev is now ranked sixth in the world and is the second-highest ranked player of anyone that was a teenager five years ago. He has won 11 titles in his career, including a very impressive four elite titles. He has been in a bit of a slump in 2019, but he still has the most impressive list of career accomplishments of anyone on this list at this.

3. Borna Coric - The Croat just reached a career-high ranking of 12 last week, which gives him the fifth-best ranking of any player that was a teenager five years ago. He has two titles to his name and a very impressive 12 wins against top-10 players. Coric has had a steady growth throughout his career without any single big breakthrough moment.

4. Andrey Rublev - Throughout the series, I was more optimistic about Rublev than most other people, so I felt somewhat vindicated by his win over Roger Federer last week. Still, he has only won one title and has a career-high ranking of 31. Injuries have been an issue, so there is still plenty of reason to believe that he will be a top-10 player in the future.

5. Christian Garin - This looked like a massive whiff for a long time, but Garin is finally starting to make a name for himself on tour. He has won two titles this year and has a career-high ranking of No. 32 in the world after breaking into the top 100 for the first time late last year. At this point, he looks like he'll never be more than a clay specialist with 28 of his 34 career wins coming on dirt, but he can make a decent career for himself that way.

6. Jared Donaldson - Just a year after getting into the top-50 in tennis, Donaldson had a right knee injury that has kept him away from tennis for over five months now as his ranking has slipped to No. 713 in the world. He has 47 career wins and is still only 22 years old. It will be a long road back for him, but his career isn't necessarily over.

7. Frances Tiafoe - Unlike five years ago, we now know the right way to spell Frances. Earlier this year, he was ranked No. 29 in the world, but has since dropped back down to No. 52. Last year, he won his only career title to date in Delray Beach and he also reached the final in Estoril. He has struggled at the majors, but has proven to be a tough draw in a best-of-3 match. Tiafoe was a little overrated at No. 7 on this list, but not by much.

8. Thanasi Kokkinakis - Most people had Kokkinakis in their top 3 or 5 this time five years ago, so I felt like I was being bold putting him as low as No. 8. Yet I still overrated him. Kokkinakis has not reached the top 50 in the rankings yet and is currently outside the top 200. Injuries have been the main reason that he hasn't lived up to potential. Kokkinakis has finally been healthy over the last month, so maybe now he can start to make a comeback.

9. Nikola Milojevic - This is another one that looked like a big bust until recently. Don't get me wrong, the former junior No. 1 is still a long way away from living up to expectations, but there have been some positive signs over the last year that he will eventually be a regular on the tour-level. He won his second career Challenger title this month and is back in the top 150.

10. Stefan Kozlov - The American has been a bust so far, but is also only 21-years old, so it's way too soon to give up on Kozlov. Still, it has been two and a half years since he reached his career-high ranking of 119 and he is now outside the top 500 despite having played in 14 events this year. All 14 events have been played in North America, which is great for saving on travel expenses, but a nightmare for trying to get ranking points.

11. Hyeon Chung - We finally get to the first underrated player on this list. While Chung has had a massive slump in 2019, he did get into the top 20 in the world last year. He has 81 career tour-level wins and there is no reason to think he won't be back in the top 20 again in the future.

12. Noah Rubin - My American bias was showing on this one. I never listed Rubin this high again on my list, although his career trajectory hasn't been that bad. He still hasn't cracked the top 100 and is currently No. 195, but he did qualify for Wimbledon this year.

13. Kyle Edmund - The Brit was definitely underrated on this list. He is the tenth-highest ranked player of anyone who was a teenager five years ago. He has been ranked as high as No. 14 in the world and has one title to his name. He has 22 grand slam wins, which is near the most of anyone on this list.

14. Gianluigi Quinzi - This was another bust. Quinzi had an impressive junior career, but it never turned into much on the professional level. He is ranked lower now than he was five years ago and he peaked at No. 142.

15. Roman Safiullin - The Russian's career so far has been totally derailed by injuries. 2019 will be his first full season as a professional and he is near breaking into the top 200 for the first time. Lots of young Russians are having success right now, and it would be great to see Safiullin join them. He's still only 22 years old.

16. Yunseong Chung - Despite having not played a single tour-level match at this point in his career, he is ranked No. 259 in the world. So far, Chung has been a bust.

17. Elias Ymer - Ymer is still trying to get into the top 100. He came very close last year and could do it this year. At 23 years old, I would have expected him to be farther along by now. I'm more optimistic about his younger brother at this point.

18. Laslo Djere - The Serb has finally started to deliver on all the hype this year. He got as high as No. 27 in the world in June after reaching the third round of Roland Garros where he nearly took out Kei Nishikori. His success has been limited to clay courts, but if you told me five years ago that he had a better career than Garin, I would have been very surprised.

19. Johan Tatlot - I had nearly forgotten about Tatlot. He still hasn't reached the top 200 yet and hasn't played a single tour-level match, so he's definitely a bust so far.

20. Nicolas Jarry - The Chilean peaked at No. 8 in his junior career, so most people didn't have high expectations for Jarry as a professional, so I'm going to give myself some credit on this one. He is currently ranked No. 69 with a career-high ranking of No. 38. He also won his first career title this year in Bastad.

Players missing: Lorenzo Sonego, Cameron Norrie, Yoshihito Nishioka, Matteo Berrettini, Karen Khachanov, Daniil Medvedev, Andrey Bublik, Hubert Hurkacz, Ugo Humbert, Reilly Opelka, Taylor Fritz, Stefanos Tsitsipas, Casper Ruud, Denis Shapovalov, Alex De Minaur, Miomir Kecmanovic, Felix Auger-Alliasime.

Of those players that were missing, the following were listed on later editions of the top 20 under 20 series: Nishioka, Khachanov, Bublik, Opelka, Fritz, Tsitsipas, Ruud, Shapovalov, De Minaur, Kecmanovic, Auger-Alliasime.

Daniil Medvedev is currently the highest ranked player that was a teenager five years ago. He was never listed in my top 20, which either shows how bad my lists were or how he came out of nowhere. His junior ranking peaked at No. 13 and he didn't reach the top 100 until he was 20. He did receive consideration for my list, but he never made the cut. He has definitely proven me wrong!