Frances Tiafoe took a major step in his young career Sunday. (Joe Skipper/Associated Press)

Last month, Frances Tiafoe’s confidence reached a low point. Early-tournament exits had torpedoed his ranking toward triple digits. His serve, typically a strength, had abandoned him on the biggest stages. “Terrible,” is how he described his serve at the Australian Open, where he suffered a straight-set defeat to his childhood idol, Juan Martin del Potro, in the first round.

Any momentum Tiafoe gained from his five-set loss to Roger Federer at last year’s U.S. Open had vanished and what remained was a young pro touted as the future of American tennis questioning where he had gone wrong.

But on Sunday, Tiafoe reversed that downward trend and put his career back on its expected trajectory by claiming his first ATP title at age 20. With the result, a 6-1, 6-4 win over Germany’s Peter Gojowczyk in the Delray Beach (Fla.) Open, Tiafoe became the youngest American ATP champion since a 19-year-old Andy Roddick won in Houston in 2002.

To get where he wanted to be, Tiafoe realized, he had to return to where it all started — his home town of College Park, Md.

“I think home is the answer for me,” Tiafoe said in a phone conversation Monday. “It’s my city. It’s where I’m comfortable.”

Tiafoe grew up in College Park, breathing in the sport at the Junior Tennis Champions Center with his twin brother, Franklin. The boys attended a program there because their father, an immigrant from Sierra Leone, worked at the facility as the maintenance man.

Both twins took to the sport (Franklin starred at DeMatha High and played for Salisbury University last year), but it was Frances who skyrocketed up the junior rankings. Photos and articles of him are plastered around the tennis center and Tiafoe remains an inspiration to the young players putting in long hours on the courts, dreaming of tennis stardom.

Tiafoe spent a week in early February with his family and friends in Maryland after losing in the second round of a challenger tournament.

“I was going through a lot mentally,” he said of his early-season slump. “Being back at the court I grew up in, being in a place everybody knows me, is the answer for me. To see my brother, see my friends, I think it builds character for me, just being accountable for myself.”

While at home, Tiafoe trained with his friend and former collegiate player, Zack Evenden. The two worked on tweaking Tiafoe’s serve and putting him “in a good head space.”

By the time he arrived at the New York Open in mid-February, Tiafoe was riding a wave of confidence. He reached the quarterfinals where he lost to reigning U.S. Open runner-up Kevin Anderson in three close sets.

Tiafoe wasn’t sure he’d be playing at Delray Beach until learning a couple minutes before his match against Anderson that he received a wild card.

He took advantage of the opportunity, beating players like del Potro, the then-world No. 10, and fellow rising stars Hyeon Chung of South Korea and Canada’s Denis Shapovalov. Chung, 21, recently reached the Australian Open semifinals; Shapovalov, 18, has attracted a devoted following with his highlight-reel-worthy winners.

“I really think he’s capable of winning Grand Slams and doing great things in the sport,” Shapovalov said of Tiafoe in a news conference after losing their semifinal, 7-5, 6-4. “He’s an unbelievable player. He showed today and throughout the week he can really hurt players and do damage.”

Before the New York Open, Tiafoe was 0 for 2 in ATP World Tour matches this season. Since turning pro in 2015, he has shown flashes of his potential but also has struggled on the bigger stages. He has yet to make a Grand Slam breakthrough like other stars of his generation.

Tiafoe, however, is done waiting. He believes his moment begins now.

“I’ve had signs I can play at the highest level,” he said. “I stayed within myself the whole week. I cut all the side noises out. … I started to take ownership of my career and I wanted to get it. I’m more motivated than ever.”

After firing his 13th and final ace Sunday against Gojowczyk, Tiafoe fell to the ground and tapped his chest. He would later run over to his box and shed a few tears as he hugged his father, Frances Sr.

Tiafoe, the world No. 61, has dreamed about this moment, and more moments like them, since he was a toddler in College Park. Next month, Tiafoe will play at Indian Wells and Miami before getting ready for the clay-court season.

Asked what his next milestone will be, Tiafoe laughed.

“Just got to sit back and watch,” he said.

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