Two star athletes – Anita Alvarez and Dana Mathewson – have been able to perform at the peak of all athletic competition, representing the United States at the Olympics. Critically, they have drawn wisdom and inspiration from mentors and others in their sport, which has been foundational in their success.

Naomi Osaka may have captured her first Grand Slam trophy on Saturday by winning the U.S. Open, but it was her opponent Serena Williams who became the center of attention after arguing with the umpire.

Serena Williams Feuds With Umpire In U.S. Open Final

In the last set of the final, the 36-year-old superstar became upset with umpire Carlos Ramos. Williams accused him of cheating and called him a “thief” for stealing a game-winning point from her. The 23-time Grand Slam champion eventually drew a coaching violation.

“You will never, ever, ever be on another court of mine as long as you live. You are the liar. When are you going to give me my apology? You owe me an apology. Say it. Say you’re sorry. … And you stole a point from me. You’re a thief, too!”

SLIDESHOW: 30 Best Sports Instagrams! 

Williams also cited her new status as a mother to insist that she would never cheat because she hopes to always set a good example for her daughter.

Osaka, a 20-year-old from Japan, defeated No. 17 seed Williams 6-2, 6-4 for her first major title, although the trophy ceremony was blemished by boos from the crowd and tears from both Williams and Osaka. However, Williams was then shown comforting her opponent, and implored the crowd at Arthur Ashe Stadium to stop booing and “stay positive.”

Though many condemned Williams for stealing the spotlight from Osaka, several prominent tennis stars and organizations rushed to defend the American star, saying a male player would not likely have been penalized for showing a similar kind of frustration on the court.

Billie Jean King, the World Tennis Association and the U.S. Tennis Association all backed Williams. King, a 39-time Grand Slam champion, said in a Washington Post op-ed she believed Williams was the victim of yet another clear example of sexism, racism and people “abusing” their authority.

“What was supposed to be a memorable moment for tennis, with Serena Williams, perhaps the greatest player of all time, facing off against Naomi Osaka, the future of our sport, turned into another example of people in positions of power abusing that power,” King said.

According to People magazine, Williams received a $17,000 fine for verbally abusing Ramos and for breaking a racket.

30 SPORTS FIGURES WHO DIED IN 2018 – TRIBUTE SLIDESHOW

“Women are treated differently in most arenas of life,” 74-year-old King continued in her piece. “This is especially true for women of color. And what played out on the court yesterday happens far too often. It happens in sports, in the office and in public service. Ultimately, a woman was penalized for standing up for herself. A woman faced down sexism, and the match went on.”

Much of the sexism that female tennis players like King faced in the 1970s and before that was portrayed in the 2017 biopic film Battle of the Sexes, in which Emma Stone played King.

U.S.TA President Katrina Adams praised Williams for her words and actions in the trophy ceremony in a statement, saying: “What Serena did on the podium today showed a great deal of class and sportsmanship. This was Naomi’s moment, and Serena wanted her to be able to enjoy it. That was a class move from a true champion.”

In the press conference after Saturday’s final, Williams insisted she believes sexism continues to pervade professional tennis.

“I’ve seen other men call other umpires several things. And I’m here fighting for women’s rights and for women’s equality.”

The USTA has granted Maria Sharapova a wild-card entry into the main draw of this year’s US Open, which will mark the Russian star’s first Grand Slam tournament since returning from a partially-served 15-month doping suspension.

Maria Sharapova doping ban news

Sharapova, 30, returned to the WTA Tour following her ban’s expiration in April, although she was not given a wild-card spot into the French Open and missed Wimbledon after withdrawing early from qualifiers with a thigh injury she initially sustained at the Italian Open in May.

The Russian — who has seen her world ranking fall to 148th — was suspended in March 2016 after testing positive for the heart medication meldonium at the 2016 Australian Open, the first tournament she participated in after the drug had been prohibited by the World Anti-Doping Agency and several other anti-doping agencies.

Sharapova’s initial ban was for two years effective after the end of the Melbourne tournament, which means she would have been forbidden from playing until Jan. 2018, but the punishment was reduced upon her appeal in October. The Russian claimed she did not know meldonium was prohibited, and that she had been using it since 2006 — the year she won the US Open — purely to treat a series of health problems including bouts of the flu, possible onset diabetes and a magnesium deficiency.

Sharapova has not competed in a Grand Slam in nearly 18 months. On Tuesday, she thanked US Open officials on Twitter for giving her the opportunity to participate in the major:

Tennis legend Billie Jean King expressed her approval of officials’ decision to issue Sharapova a wild card in her own tweet:

“Her suspension under the terms of the tennis anti-doping program was completed and therefore was not one of the factors weighed in our wild card selection process,” the USTA said of Sharapova in a statement. “Consistent with past practice, a wild card was provided to a past U.S. Champion who needed the wild card for entry into the main draw.”

In its statement, the USTA also listed former US Open champions who previously received main-draw wild cards, including Martina Hingis, Lleyton Hewitt, Kim Clijsters and Juan Martin del Potro.

Seven other players besides Sharapova were awarded wild card entries into the 2017 US Open, including two Americans:  Taylor Townsend and Kayla Day. 

At this year’s Open — which begins on Aug. 28 in Queens, New York — Sharapova will also be talking to young tennis players about anti-doping regulations and about how crucial it is to respect the USTA’s rules with respect to drugs and other issues.

“Additionally, Sharapova has volunteered to speak to young tennis players at the USTA National Campus about the importance of the tennis anti-doping program and the personal responsibility each player has to comply with the program’s requirements,” the USTA statement said.

The U.S. Open wild card is the tenth Sharapova has been given this year. She earlier received them to gain entry into the first four tournaments she played this year (in Stuttgart, Madrid, Rome and Stanford, Calif.). She also received wild cards into several tournaments she was forced to miss due to injury (Birmingham, England; Toronto and Cincinnati) and for two events she plans to play in China this fall.

“I’m very fortunate and grateful for the tournaments that have provided me a wild card, and I’d say 99 percent of them have at this point,” Sharapova said two weeks ago at the Bank of the West Classic in Stanford, California. “So I’m very thankful. A lot of these events I’ve played at before, and I have a history with the people, the fans, the tournament itself. So the opportunities that I have, I’m taking it. I want to perform, and I want to perform well, and it means a lot to me to be there.”

Sharapova withdrew from the Bank of the West Classic due to soreness in her left arm.

The Russian’s last major title came in 2014, when she won the French Open. Sharapova also reached the US Open semifinals in 2012.

Caption:MELBOURNE, AUSTRALIA – JANUARY 22: Maria Sharapova of Russia plays a backhand in her third round match against Lauren Davis of the United States during day five of the 2016 Australian Open at Melbourne Park on January 22, 2016 in Melbourne, Australia. (Photo by Ryan Pierse/Getty Images)