Serena Williams at the U.S. Open: Along with Venus, she was a ‘game changer.’

In 1998, when Serena Williams made her singles debut at the U.S. Open, it was typical to see a crowd of many white faces watching many white players.

In the years since, she has done more than any other person to transform those tournament grounds in Queens into a more inclusive environment, where increasing numbers of women and girls of color, some of whom have gone on to play and win in the event, join in the fun each year.

While emerging as the face of tennis, Williams, along with her older sister Venus, changed the faces of tennis.

“It’s a great feeling to see it,” said Martin Blackman, the general manager of player and coach development for the United States Tennis Association. “I attribute that to Serena and Venus. They completely changed the narrative.”

Blackman’s father attended the U.S. Open in Forest Hills, Queens, to see Althea Gibson in the late 1950s, and was one of three Black fans in attendance, he told his son. When Blackman went to the U.S. Open for the first time 20 years later as a fan, there were more Black spectators than the amount his father saw, but nothing like now, thanks largely to the Williamses. Blackman went to the tournament later, as a player representative in 1999, the year Serena won her first major singles title at age 17.

“I had the privilege of working in the junior space at that time, and I gradually started to see more and more African American girls and African American boys coming to our camps,” he said. “And the common thread was the inspiration and demonstration effect that Serena and Venus provided. That was the inflection point. That was the game changer.”

Over a quarter-century, Serena Williams came to dominate the U.S. Open, winning six singles titles and reaching four other singles finals; winning two doubles titles, with Venus; and winning a mixed doubles title. She also flamed out in spectacular fashion on more than one occasion.

For each title, there were untold numbers of players, like Sloane Stephens, Madison Keys, Naomi Osaka, Coco Gauff and others, whose passion for the game was ignited by Williams’s fiery and unapologetic charisma.

There were groundbreaking victories, shocking losses, emotional outbursts and hours of thrilling, inspiring tennis, all of which is coming to an end. Williams wrote in a cover story for Vogue magazine, published online Tuesday, that she was transitioning away from tennis to focus on other pursuits, including growing her family.

“I started playing tennis with the goal of winning the U.S. Open,” she wrote.

She attained that goal, and plenty more. In an era of the sport when American men faltered, she more than carried the load for the nation’s tennis aspirations.

Williams was 16, beads in her hair, when she played her first U.S. Open singles match, beating Nicole Pratt and making it to the third round. But being Serena Williams, she did come away with a title, winning mixed doubles with Max Mirnyi.

“Even at that age you could see her talent and athleticism,” Mirnyi, 45, recalled. “I would notice, every time she went back to strike the ball, the opponents would be back on their heels. They literally backed up.”

Mirnyi’s father, Nikolai, was responsible for arranging the pairing two months earlier at Wimbledon. He asked Richard Williams, Serena’s father, and within days the two had won their first tournament. The only things that could stop them, Mirnyi felt, were the warnings and point penalties chair umpires would impose when beads fell out of Williams’s hair and onto the court.

“I kept saying, ‘We don’t want to lose any points because of the beads,’” Mirnyi recalled. “And she would just say, ‘Oh, it’s OK.’ And it was.”

But a singles title was her mission. Her first major singles championship came at the 1999 U.S. Open when she beat Martina Hingis in the final at Arthur Ashe Stadium to become the first Black woman to win a Grand Slam event since Gibson, who won five, including the 1957 and 1958 U.S. Opens.

Upon winning, she put her hands to her heart and could be seen saying, “Oh my God, I won, oh my God.” Later, she spoke to President Bill Clinton and his daughter, Chelsea, by telephone.

In 2001, fans saw the first of the awkward Williams sister duels at a major final, won by Venus Williams. The next year, Serena Williams captured rematches at the French Open, Wimbledon and the U.S. Open.

It would be six years before she beat Jelena Jankovic for the 2008 U.S. Open title, which was followed in 2009 by an on-court flare-up that abruptly ended her semifinal match with Kim Clijsters. Williams had been called for a foot fault that set up a match point, then accosted the lineswoman. Williams was assessed a point penalty, which gave the match to a stunned Clijsters, who went on to win the tournament.

Williams won three straight titles beginning in 2012; in 2015, she entered New York looking unbeatable. She had won the three previous major events that year, and winning the fourth would have given her the coveted Grand Slam. But the pressure proved too much, and she was upset in a semifinal by an unseeded Italian, Roberta Vinci.

Her 2018 Open final, against Osaka, was marred by a lengthy and intermittent dispute between Williams and the chair umpire, Carlos Ramos, who initially set off the uproar by calling a code violation on Williams because her coach was signaling to her from the seats. The argument ensued over two changeovers and resulted in her losing a game, and her focus, allowing Osaka to take her first major title amid a cascade of boos and jeers.

The spectators were squarely on Williams’s side, and still are. On Tuesday, after news broke that Williams is retiring, 13,000 tickets were sold by 3 p.m., the U.S.T.A. said. As it has been for years, fans will flock to the U.S. Open again, because Serena, along with Venus, made Flushing one of the premier spots in the country to see a celebrated, groundbreaking Black hero in person.