John McEnroe seeked out this ATP player to be the next star of American tennis back in 2011.
There has not been an American men’s singles Grand Slam champion in over 21 years, with the last coming when Andy Roddick won the 2003 US Open.
The closest that drought has come to ending is last year, when Taylor Fritz reached the US Open final before losing to Jannik Sinner.
However, before Fritz came on the scene, McEnroe picked out a young ATP player that he thought could be a potential contender at the top of the sport.
Photo by Morne de Klerk/Getty ImagesJohn McEnroe claimed Ryan Harrison would reach the ATP top 10
On April 14 2008, 15-year-old Ryan Harrison would make his ATP main draw debut after qualifying for the U.S. Men’s Clay Court Championships in Houston.
Ranked 1277 in the world at the time, Harrison would cause a big shock and beat world number 95 Pablo Cuevas, 6-4 6-3.
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As a result, he became the 10th youngest ATP match winner in history at just 15-years-old and 11 months.
This record still stands, with the now retired Rafael Nadal just ahead of Harrison by one month, after he won his first match at the 2002 Mallorca Open.
Some of the other players sitting above Harrison include Grand Slam champions Andre Agassi, Bjorn Borg and Mats Wilander.
Harrison would lose his subsequent match against top seed James Blake, and would spend the next year competing on the Challenger Tour.
Three years on from his debut win, a 19-year-old Harrison was a mainstay on the ATP Tour and had broken into the top 100 following reaching his first semi-final at the Los Angeles Open.
Someone who knows a thing or two about success is seven-time major winner John McEnroe, who appeared to be impressed by his rising compatriot.
When speaking on a ESPN conference call ahead of the 2011 US Open, McEnroe predicted Harrison to approach the top 10 of the ATP rankings.
“Ryan Harrison to me has always been a guy that you know he’s going to be a top 10, top 15 player, but can he get to that top elite game?” questioned McEnroe. “That remains to be seen for me.
“But I like him for what he’s bringing to the table now, and he loves to be out there competing and he’s learning. He’s going to get up there. It’s just how much is he going to develop his own sort of personality and game would be my question.”
Harrison would subsequently lose in the first round of the 2011 US Open to 27th seed Marin Cilic, and he would not have the career that many expected him to from this point.
Photo credit should read STAN HONDA/AFP via Getty ImagesWhat happened to Ryan Harrison?
Harrison would reach four ATP singles finals in his career, but his only title came at the Memphis Open in 2017.
This was the same year that he would reach his career-high ranking of world number 40, much lower than what McEnroe thought Harrison could achieve.
Harrison’s Grand Slam singles results were not much to shout about either, with his best coming at the Australian Open and US Open where he reached the third round.
However, Harrison did find some major success in doubles, winning Roland Garros alongside New Zealander partner Michael Venus in 2017.
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While it is unclear exactly why Harrison was unable to achieve his potential, the American had years of injury problems.
This included undergoing surgeries to injuries to his wrist, femur, hip, shoulder and abductor muscles.
Harrison announced his retirement in 2024 at the age of 32, citing these injury struggles and health problems as his reasoning for ending his on-court career.
Since then, the once promising young talent has coached Danielle Collins and has also partaken in media activities.