Former youth sensation Tommy Paul beginning to realize potential at Australian Open

Tommy Paul was the French Open's junior champion in 2015. After years of injuries and growing pains, he's finding success on the court at the Australian Open. Mike Owen/Getty Images

The image remains fixed in memory, like one of those perfect snapshots that you never throw away: Tommy Paul, 18 years old, and Taylor Fritz, 17, junior champion and runner-up respectively at the 2015 French Open. They're grinning as they pose for the camera, the Stars and Stripes draped like a cape over their shoulders, on the since-demolished Court No. 1 at Roland Garros.

The future looked brighter than the dazzling silver trophies they each held on that bluebird day, and in some ways it was -- at least for Fritz. Less than a year later, he became the youngest American to reach an ATP Tour event final since Michael Chang in 1988. He was quickly identified as one of the elite "Next Gen" group projected to pick up where Roger Federer & Co. eventually leave off.

A different, less sunny fate awaited Paul. There were fitness issues and two significant injuries, along with emotional growing pains that prevented Paul from keeping pace with his friends Fritz, Frances Tiafoe and Reilly Opelka.

"I made some decisions in the past that I would take back now," Paul told ESPN.com shortly after he earned a French Open wild card last spring, a critical step in his ongoing rejuvenation. "I'm just investing more in my career now, taking everything more seriously."

The payoff to Paul's restored health -- and newfound dedication -- arrived on Wednesday at the Australian Open, where he reached the third round at a major for the first time in his career with successive, down-and-dirty wins that went the five-set distance. The most recent was a four-hour, 19-minute marathon conquest of No. 18 seed Grigor Dimitrov, Paul sweeping the fifth-set super-tiebreaker 10-3.

"I've never really played back-to-back best-of-five matches," Paul told the Australian fans whose support helped pull him through. "I guess if you're going to have a second one, why not go 7-6 in the fifth?"

Paul wasn't the only hardscrabble player from the U.S. to punch through, either. Tennys Sandgren, a bearded Tennessean, barreled onto the pro scene unannounced in 2017 at age 25. He won his first ATP title a year ago at Auckland. He also struck a significant blow to the seedings in the second round Wednesday, taking out No. 8 Matteo Berrettini in another five-set thriller.

Sandgren, a surprise semifinalist at the Australian Open in 2018, struggled with injury and played only one tour-level match between the US Open in September and the start of this year. After this latest win, his third over a top-10 player in the first major of the year, Sandgren told the ATP media staff, "Sometimes you can get lost a little bit when you're playing 30 or 35 weeks a year. I feel my game comes together in these [Grand Slam] weeks. I'm getting get better at that. Maybe I'm just getting older and wiser."

Unfortunately for U.S. fans, Sandgren will next square off against another resurgent American, former Wimbledon semifinalist Sam Querrey. Paul has a slightly less daunting assignment in another third-round greenhorn, a first meeting with No. 67-ranked Marton Fucsovics.

Paul's flush of success in Paris in 2015 was less a sign of his clay-court prowess than his athleticism and innate adaptability. Born in New Jersey not far from Philadelphia -- he calls himself a Sixers and Eagles fan -- he was still an infant when his family moved to North Carolina, where his stepfather owned a multipurpose sports complex. Paul developed his game on the Har-Tru (green clay) courts at that club.

"It was pretty funny," he said. "I would be playing all these hard-court tournaments as a junior but trained for them on clay, all the way up until I left in the car to go play them."

"I made some decisions in the past that I would take back now. I'm just investing more my career now, taking everything more seriously." Tommy Paul

Paul's athleticism and familiarity with Har-Tru accounted for his eventual proficiency on the more popular, if somewhat different, red clay. That gave him a slight advantage over some of his peers. While he felt equally comfortable on hard courts, it was the other bits that go with becoming an impact player on the pro tour that tripped up the nimble, lean 6-foot-1 right-hander.

"I was pumped up, definitely ready to make the jump to the pros," Paul said. "But I expected it to be a lot easier."

Apart from the entitlement he felt after that dream run to the French junior title, Paul soon discovered that even a muscular, tensile young body could not hold up to the demands of the pro tour without a disciplined, comprehensive training regimen. Building on his junior success at the tour level proved more difficult than Paul expected. He pushed it, making slow progress, but eventually things broke. A "stress reaction" elbow injury sidelined him for five months earlier in 2018; early in 2019, a quadriceps/knee injury knocked him out for three months.

"I didn't underestimate how strong you needed to be," he said. "It was more about learning to take care of my body, doing the stretching, cool downs, all the professional stuff."

Diego Moyano, a USTA national coach, shepherded Paul through his early pro career. Moyano left to become Kevin Anderson's coach late last year, with veteran Brad Stine taking over as Paul's mentor. Moyano engineered the turnabout that has helped Paul lift his ranking from outside the top 200 at the start of 2019 to No. 90 at the start of 2020. Paul is quietly off to a great start this year; he's 7-1, including a trip to the semifinals at Adelaide.

Moyano told ESPN.com in an interview that it took Paul longer than some of his peers to "figure out" the obligations of the pro life. But the two also did intensive work on his serve.

"Before, Tommy's average serve speed was 105 mph or so," he said. "We brought that up to between 114 and 124 mph, but he can hit up to 134 and 136 max."

Paul's fastest against Dimitrov was 134, one mph better than his opponent's best.

Paul has plenty of upside left, according to Moyano. It's now up to Stine, who had a long, fruitful tenure with former No. 1 Jim Courier, to help Paul reach his ceiling.

"I love his [Paul's] spirit," Stine wrote in an email shortly after his protégé eliminated Dimitrov. "He has a passion for the fight. I see some real similarities with Jim [Courier] in that regard. The match with Grigor really highlighted his determination, drive and willingness to suffer. All things Jim had in spades."

Said Moyano: "There's a lot of room for improvement. Tommy's a great athlete. He can clean up his movement, his transition game and volleys could be way better. His serve speed is good now but her first-serve conversion should be up around 65% (it's currently at 62%). He has the smooth motion, the good toss, everything to be there."

The trigger for Paul's newfound clarity of purpose was partly the success of his peers. Tiafoe made the Australian Open quarterfinals in 2019; Fritz and Opelka both won their first ATP titles last year. Replacements for Federer or Rafael Nadal? Not hardly. But they hit ranking highs of No. 31 (Opelka) or better.

"For a long time, that success by the others never bothered Tommy," Moyano said. "He has a good heart, he likes to see his friends do well. But it got to the point where he started thinking, 'Hey, I belong in that group. I have that level. Why am I not there?'"

Ultimately, fellow outsider Sandgren played a major, if unwitting, role in Paul's big push last year. Already a former Australian Open quarterfinalist, Sandgren dropped down to the Challenger level last year to try to rebuild his confidence following a slump. Paul beat him in back-to-back Challenger events (Sarasota and Tallahassee), a performance that earned him a wild card into French Open. Paul had the bad luck to draw Dominic Thiem in the former junior champion's first main-draw match at Roland Garros. It had proved to be a long, hard road back to Paris, but by the time Paul got there, he was a different, battle-hardened competitor.

"He's a very balanced 22-year-old," said Stine, who added that Paul has embraced all the adjustments -- "whether technical, tactical, mental or emotional" -- that they've worked on thus far. "He's committed to improving -- and proving to himself that he belongs alongside the rest of his friends."

Paul and Sandgren could theoretically meet in the quarterfinals, but that's the last thing on either man's mind. For now, the thrill of surviving long matches against elite rivals is satisfaction enough, especially when the feat was accomplished, as in Paul's case, on Margaret Court Arena (capacity 7,500) before an enthusiastic crowd that kept chanting his name. The refrain rolled down like gravel in a chute after critical points: "Tom-my! Tom-my! Tom-my!"

After he won, Paul told those fans: "I've never been a part of something like that, honestly. [I had] a lot of fun playing in front of all you guys. Towards the end of the fifth, it was you guys who got me through it."

For Paul, it was a match full of unforgettable moments. The kind that made memories like snapshots you won't ever discard, or forget.