Tommy Haas, the thirty-eight-year-old German tennis player, was once one of the top players on the A.T.P. tour; he is now one of the oldest. He is also now the tournament director of the BNP Paribas Open, at Indian Wells—the kind of corporate job typically held by people known for their operations-management skills, not for their flowing one-handed backhand. Last Thursday, at 9:15 in the morning, Haas was driving to the grounds of Indian Wells, hoping to get a hit in—he was planning to play in the Miami Open, which began a few days later—when his phone rang. Nick Kyrgios, a talented and mercurial twenty-one-year-old Australian, had been up all night, feeling ill; he thought it was food poisoning. Kyrgios was due to play Roger Federer in the quarter-finals at noon, in what was to be the marquee match of the day, and perhaps of the tournament.

Practice was forgotten. Haas spent the next forty-five minutes on the phone with the tournament referee and the doctor who was sent over to Kyrgios’s hotel, and discussing the situation with the management team at Indian Wells. At around ten, Kyrgios decided that he was unable to play. Haas found Federer in the locker room, told him the news, and then scrambled to find a way to appease thousands of ticket holders. Federer would come on court and say a few words to the crowd. Haas had the idea of showing a music video of himself, Federer, and Grigor Dimitrov singing “Hard to Say I’m Sorry,” written by Haas’s father-in-law, the songwriter David Foster, who accompanied on the piano. Haas reached out to players still in town to see if they would play an exhibition. It was after noon.

By then, the crowd had heard the news. Most people were milling around outside; there was a line to get into some of the shops, while the stadium was not even half full. Still, a big cheer went up when Federer appeared, as it always does. Federer said a few unmemorable words and introduced the video. Then Haas went out onto the court, wearing his cap backwards, as usual, and played a practice set with Vasek Pospisil, a twenty-six-year-old Canadian ranked a hundred and twenty-ninth in the world. Pospisil had upset the No. 1 player, Andy Murray, in the second round, and then lost to a player ranked outside the top hundred. In front of the smattering of fans who had stuck around, Haas won. He left the court and the tournament went on.

This is where tennis is these days: swinging between chaotic uncertainty and familiar sublime heights. Pospisil’s defeat of Murray, for instance, had been a surprise but not a shock; for whatever reason, Murray has never excelled at Indian Wells. Still, it seemed to have larger meaning—just as it was impossible not to view Kyrgios’s withdrawal as part of a wider narrative of tennis’s current instability. For the past decade, men’s tennis has been almost entirely dominated by four players, and women’s tennis by one. Serena Williams just won her twenty-third major title; on the men’s side, Federer, Rafael Nadal, Novak Djokovic, and Murray have combined to win forty-three out of the past forty-eight. This year, though, Murray lost early at Indian Wells; Djokovic went down to Kyrgios; Nadal was soundly beaten by Federer; and Williams, citing injury, did not come at all. Williams and Federer are both thirty-five years old. There is a cohort of strong young players, but none of them has emerged as the obvious successor to Williams or the Big Four. The future doesn’t always show up when you want it to.

Haas, whose career has been repeatedly derailed, may understand tennis’s essential uncertainty better than most. Born in 1978, in Hamburg, Haas moved to Florida as an adolescent to train at the Nick Bollettieri Academy. When he turned pro, in 1996, he established himself immediately, making the quarter-finals of his first A.T.P. tournament, where he lost to Pete Sampras. Still, he had a powerful baseline game, and by 2002 he was ranked No. 2. He had winning records against several former and future No. 1s, including Federer, whom he played, and beat, for the first time in 2000, in the semifinals of the Sydney Olympics.

“You start to feel invincible,” Haas told me, sitting in his office in Indian Wells on Saturday morning, the day after his impromptu exhibition. He leaned back in his chair, speaking quickly with a clipped German accent. “Then my shoulder blew out, and I was gone for fifteen months, and it’s a whole other ball game.” By the time he returned, in 2004, Federer was No. 1. Then Haas suffered another string of injuries. He had problems with his elbow, ankle, hip, and foot. In all, Haas has had nine surgeries. He returned to play after each one, and even made it back to the top ten in 2007, but was already thinking about what could come next. “When you pick up a racquet as a three-year-old, when it becomes your dream at the age of seven to become a professional tennis player—” His eyes flicked to the television screen on the wall, where Federer and the twenty-four-year-old American Jack Sock were warming up for the semifinal. “Tennis is what I know,” he said. Haas, who became a dual citizen in 2010, now lives in Los Angeles, with his wife, the actor Sara Foster, and their two young daughters. He told me that he thought his “next day job” might be “taking over as a home dad.”

The BNP Paribas Open is one of tennis’s biggest events; it draws nearly half a million fans and has won the Tournament of the Year award from both the W.T.A. and A.T.P. tours for three years in a row. It’s sometimes called “the fifth Slam.” Haas became interested in the job of Indian Wells tournament director in 2015, when he heard that Steve Simon was leaving the position, to lead the W.T.A. Haas was already good friends with Larry Ellison, the tournament’s owner; Haas stayed with him while he was playing in Indian Wells, and they frequently talked about the tournament. But Raymond Moore, who was already the chief executive of the tournament, got the job. He lasted for less than a year. “Due to another circumstance, I guess, the door just opened up,” Haas told me. He was being circumspect. Moore resigned last spring after he told reporters that he thought female players rode on the “coattails” of the men. (“They are very, very lucky,” Moore had said. “If I was a lady player, I’d go down every night on my knees and thank God that Roger Federer and Rafa Nadal were born, because they have carried this sport. They really have.”)

After Moore left, the tournament was in damage-control mode. Haas—charismatic, articulate, and photogenic—was popular among players and fans alike. No one expected him to be as intimately involved in running the tournament as Steve Simon. Haas has played only intermittently in the past few years because of his injuries, but this year he played Delray Beach and Miami; soon, he’ll be in Monte Carlo, Madrid, and Rome, playing through the summer, when he says he will retire. He spends much of his time during the tournament, he says, talking to visitors and sponsors and soliciting feedback. The rest is out of his control.