Youth tennis clinics, like the one reigning U.S. Open champion Sloane Stephens is holding for some two dozen children in Washington, D.C., on this stifling summer afternoon, tend to be lighthearted affairs known in the trade as a hit and giggle. Pro player lobs a few shots to the kiddies, waves to the cameras, signs some autographs. Sponsor gets exposure, star gives back, kids pick up some tips–everyone goes home happy.
Stephens, however, doesn’t like such “foo-foo”–her words–affairs. “Hustle!” she yells at a group of 11-year-olds not moving fast enough for her liking. “Come on, pay attention!” she barks when eyes wander. “Hey, hey, hey,” Stephens says when some kids balk at her command to run sprints on the indoor courts. “You guys are going to have an attitude when you didn’t finish what you started?”
During a break, one girl walked to the sideline. “They said she was going to be nicer,” she griped to her mother.
A few hours later, Stephens is sitting sideways on a hotel lobby couch and laughs when I relay the young girl’s words. “I want to see you hit, I want to see your strokes, I want to see you run,” Stephens, 25, says of her tough-love approach. “If I’m going to spend an hour-and-a-half of my time, we’re going to get sh-t done.”
Lately, no other American woman not named Williams has gotten more done on the tennis court than Stephens. Last September in New York, she became the first American player–male or female–besides the Williams sisters to win a major tournament singles title in 14 years. That she did it after missing nearly a year because of injury and about one month removed from being ranked 957th was particularly striking, as was her reaction. “Oh my God,” Stephens was caught mouthing on TV before receiving the $3.7 million winner’s check. When asked then if her first Grand Slam title made her want more, Stephens spared all cliché: “Of course, girl. Did you see that check that lady handed me?”
The title raised hopes that Stephens could be the heir to the Williams’ mantle, and she has since given more reason to believe it. In March she won the Miami Open, a top tournament one notch below the four majors, and she reached the final of the French Open in June. She’ll start the U.S. Open on Aug. 27 as the third-ranked player in the world.
Every highlight, however, seems to be accompanied by a baffling flame-out. After winning the Open, Stephens lost eight straight matches. She was eliminated in the first rounds of the Australian Open and Wimbledon. Three days after her clinic in Washington, she lost to an unseeded player at the Citi Open in D.C.
Inconsistency has dogged Stephens throughout her career, and it casts a long shadow over her title defense in Flushing Meadows. Who will take the court in Queens? The future of American tennis, with electrifying speed and a smile made for Madison Avenue? Or the enigmatic should-be superstar who’s prone to unforced errors? “It’s not going to be easy,” says Stephens, discussing her state of mind before the Open. “But at the end of the day, it’s all an experience, right?”
Stephens announced her arrival in 2013, when, at 19, she upset Serena Williams in the Australian Open quarterfinals. She lost in the semis, but no matter: many tennis fans were instantly drawn to her potential and charisma. Her mother Sybil Smith is a school psychologist and the first black woman to be named a first-team All-American collegiate swimmer; her father John Stephens was a former NFL running back who died in an auto accident in 2009. Smith split with Stephens when their daughter was 18 months old. In 1994, John Stephens pleaded guilty to rape, and was facing a separate sexual-assault charge at the time of his death. Stephens reconnected with her father a few years before his death and didn’t learn about the assault cases until after. She chooses to remember the man she got to know. “I wish he could come to a tournament and see my play now,” says Stephens. “I know he’s there. He’s watching.”
The high expectations following her upset of Williams weighed on Stephens. “I felt really disappointed when I wasn’t delivering, and that kind of brought me down more than it would have normally,” she says. Among tennis cognoscenti, she developed a reputation for indifference. “All you can hope at this point is that Sloane Stephens has a hard time sleeping tonight,” the broadcaster Mary Carillo said during Stephens’ 6-1, 6-0 loss to Caroline Wozniacki at the 2014 Sony Open in Miami. After managing to win four tour events in 2015 and ’16, Stephens withdrew from the ’16 U.S. Open because of a foot injury.
Surgery and recovery kept her off the tour for 11 months. Stephens didn’t fare well in her return, at Wimbledon, but impressed at the tune-up tournaments before the Open. Soon, she was enjoying the perks of being a Grand Slam champion: an appearance on Jimmy Kimmel Live!, pictures with Magic Johnson, lucrative endorsement deals with Nike, Mercedes-Benz, Colgate and Built with Chocolate Milk. She walked the ESPYs red carpet, and won Best Female Tennis Player honors.
Following the Open, Stephens kept entering tournaments despite nursing a sore knee, reluctant to miss more time after her long layoff. The results were dismal: eight straight defeats, including in the first round of the Australian Open. The courtside chatter turned, again, to whether Stephens had what it takes to be great. Tennis legend and ESPN analyst Chris Evert, for one, publicly questioned if Stephens had the desire to win more Grand Slams.
Stephens takes the criticism in stride. “Everyone was, ‘Oh my God, what U.S. Open champion loses eight matches in a row?'” she says from the couch in the Washington hotel. “I was like, ‘Me!’ It’s going to be fine.”
Stephens has a coolness that can be mistaken for ambivalence. But she has always managed her career on her terms. In late 2017, she finished the requirements for a bachelor’s degree in communications from Indiana University East’s online program. She didn’t mind missing practice to tend to her studies, and ignored whispers she was loafing on the tennis court. “Bro, I’ve got to graduate,” she says of sticking to her timeline, no matter the consequences. “This is important, O.K.” She’s now pursing an online MBA.
Stephens is defiant about sticking to her chosen path. “I’ve been pretty harshly judged for always doing what I wanted to do,” she says.
Some critics are coming around. Evert says she now sees determination in Stephens’ eyes. It helps that she’s regained her winning form, reaching the finals of the Rogers Cup in Montreal just a few weeks before the start of the Open. Stephens knows she’ll face additional pressure as the defending champion. But she insists she’s ready to handle it.
“I’m in a good place,” Stephens says before leaving the hotel for dinner with her coach. “People say, Oh, you’re inconsistent, you’re this, you’re that. Whatever. When I retire from tennis, I’ll be able to look back and say I did it the way I wanted to do it. I was just playing. And I was just making sure I was happy along the way.”
This appears in the September 03, 2018 issue of TIME.