Fifty years ago, the men boycotted Wimbledon. That changed everything.

Stan Smith’s 1972 Wimbledon Cup sits next to his 1971 United States Open winner’s prize in a trophy case at his home in Hilton Head Island, SC. Smith had hoped to defend his title in ’73.

“I played the best tennis of my life,” said Smith, who had lost to John Newcombe in the 1971 Wimbledon final in five sets and then defeated Ilie Nastase in the 1972 final, also in five sets. “Once you’ve won it, you always want to win it again.”

But in 1973, Smith decided not to play. Instead, he and 80 other players voted to boycott the tournament just before the first games in support of player Nikola Pilic. Pilic had been banned from the tournament by the International Lawn Tennis Federation, now the ITF, the world governing body of tennis that organizes all Grand Slam tournaments, for refusing to play a Davis Cup match for his native Yugoslavia a month earlier. “It was really hard,” Smith said in a telephone interview.

As the Women’s Tennis Association celebrates the momentous 50th anniversary of Wimbledon this year in which Billie Jean King encouraged her fellow players to form the organization, the Association of Tennis Professionals is also recalling a turning point in its own history. It was when the members came together, flexed their muscles and walked away at the most prestigious tennis tournament, with repercussions that are still felt today. Among them: better communication between the players and the tournaments, and a wider distribution of prize money at all levels of the pro game.

“This was the beginning of the ATP and players coming together because it really tested the relationship,” Andrea Gaudenzi, the current ATP president, who was born a month after the boycott, said via video call. “Everyone was surprised by the support Niki received. And that made the players think that when we come together, we are powerful and can do something. That was a very important milestone.”

While the male group of players had been established a year earlier, the men were still in power struggles between the members and the tournaments. Many of the top players were committed to World Championship Tennis, a professional circuit founded in 1968 and backed by Texan businessman Lamar Hunt. The tour competed with the International Lawn Tennis Federation.

The ATP’s first group of players, called the Handsome Eight, consisted of Cliff Drysdale, Pilic and Newcombe. Arthur Ashe, Rod Laver and Ken Rosewall soon signed on.

In 1971, the federation, in an effort to maintain control over the players, voted to bar all participants of the rival World Tennis Championship from the federation’s major events for 1972, including the French Open and Wimbledon. The ban only lasted a year and sparked animosity from players.

Pilic and his doubles partner, Allan Stone, qualified for the 1973 WCT Masters, but the event coincided with a Davis Cup quarter-final tie between Yugoslavia and New Zealand. Pilic chose to play the World Tennis Championship, enraging Yugoslavia, who subsequently lost to New Zealand.

The Yugoslav Tennis Federation asked the International Lawn Tennis Federation to act against Pilic. The federation suspended him for nine months, but that was reduced to one month, just long enough to miss Wimbledon.

“If I had played, we probably would have won easily,” Pilic said of the Davis Cup over the phone from his home in Croatia. “There was a big fight with the [Yugoslav] federation” and then with the lawn tennis federation. “They could do whatever they wanted. We had no control over the sport. We had to do something.”

When the players gathered in London for Wimbledon, there were countless discussions and late-night meetings. Laver, the four-time champion, said he would not compete. So did the three-time winner Newcombe, as well as Smith, Rosewall and Ashe.

“We had to feel the pulse of the players,” Drysdale, the ATP’s first president, said over the phone. “We were professionals and we wanted to stay that way. Niki had the right to play wherever he wanted. There was no resistance to what we were doing. We never wring our hands and wonder if we did the right thing.”

At 9 a.m. on the morning of the first day of play, Drysdale called the tournament umpire, Mike Gibson, asked him if he had a pen and paper, and began to read out the names of the 81 men who would no longer compete, including 12 of the 16 seeds. By the time play started hours later, there were 29 qualifiers in the draw and 50 lucky losers, men who had lost in the qualifier but were suddenly awarded a spot in the main draw.

There was some opposition to the players’ plan to withdraw. Nastase, who had finished second to Smith the previous year, chose to compete. So did Roger Taylor, whom Pilic said he refused to talk to a year later.

Jimmy Connors also played, and Bjorn Borg, then just 17, also played his first Wimbledon.

Jan Kodes, a two-time French Open champion from Czechoslovakia, also chose to play and won his only Wimbledon. He defeated Alex Metreveli of Russia in the final.

“Nobody asked me to support the boycott,” Kodes said via email. “I was not an ATP member, so I was not in the room. No one believed this would happen. In my opinion it was pushed by the newly founded ATP to show and increase the power of the players.

“I’m not sure the boycott was really necessary,” added Kodes, who reached the US Open final two months later. “There are many controversial situations and problematic decisions in tennis.”

Drysdale, the former player, said the boycott had a long-lasting effect.

“It changed the game forever because nobody ever forgot what happened that year,” he said. “And we are all aware that it could happen again depending on how the players are treated.

“Everyone knows that the players walked out of one of the most important tournaments in the world once and no one will ever be sure they wouldn’t do it again.”

Gaudenzi said he believed unity between players was important to the growth of the game. What he would like to see now is more synergy between the ATP, the WTA, the ITF and the Grand Slam tournaments.

“We need to come together and work much more closely together,” said Gaudenzi, who did not say there should be one commissioner for the men’s and women’s tours. “I want tennis to get bigger. I want tennis to be relevant to other sports and other entertainment. We have to adapt to the new generation, the new technology, the new way fans consume the content and the competition. So we need to step up our game, and the only way to do that is to come together.”

Pilic, now 83, still marvels at the huge sacrifice his fellow players made for him.

“At the time I thought, maybe Niki Pilic isn’t that important,” he said. “But we were the products and you can’t have the tournament without the products. People couldn’t believe we did it. But we proved at that point that we were a really strong group. We lost that year, but the war has been won.”