Entertainment Sports Coach Patrick Mouratoglou Says Serena Williams Won’t Retire Until She Wins: 'She Doesn't Quit' The tennis star is only one Grand Slam victory away from tying Margaret Court, who won 24 titles in her career By Conchita Margaret Widjojo Published on February 22, 2021 12:06 PM Share Tweet Pin Email Photo: Daniel Pockett/Getty Images Serena Williams isn't done yet. Shortly after her heartbreaking loss to Naomi Osaka in the 2021 Australian Open semifinal, there was speculation that 23-time Grand Slam champion Williams was nearing the end of her incredible run. Patrick Mouratoglou, who has been Williams' coach since 2012, doesn't believe retirement is on the horizon for the athlete, however. "I don't think she will stop until she at least wins a Grand Slam, because she came back to win Grand Slams," Mouratoglou tells PEOPLE, referring to the tennis star's return after giving birth to daughter Alexis in 2017. "She doesn't quit." Serena Williams Honors Olympic Great Florence Griffith Joyner in One-Leg Catsuit at Australian Open Exiting the court after her loss on Wednesday, Williams received a standing ovation from the crowd, which she accepted warmly, waving to fans and placing a hand over her heart. The moment led commentators to discuss her tennis legacy and question whether it would be Williams' last time at the Rod Laver Arena. When a reporter at the press conference asked if it was a "farewell," the tennis star, who turns 40 this year, simply responded, "I don't know. If I ever say farewell, I wouldn't tell anyone." A few minutes later, a visibly teary-eyed Williams ended the conference early. "I don't think she planned [retirement] for this certain moment. She's dedicated all her life to tennis since she was a kid," Mouratoglou says. "So the day she will retire, she will feel like she's giving an end to 40 years of a life." Serena Williams on How Getting Married, Starting Family Helped Her Realize There's 'More to Life' "It's something that is difficult to measure for people," he continues. "That's why it's very sensitive. That's why it's very emotional for her. I completely get it." Williams is currently one title away from tying Margaret Court, who won 24 Grand Slam women's singles titles, making her the most decorated female tennis player in modern history. With three more major tournaments this year, there's always a possibility Williams will soon be able to tie, or even surpass, Court. Mouratoglou thinks it could happen. "I have to believe it and she has to believe it, too. If she [doesn't], she would stop. After all she's achieved in her career, at her age, having a baby for the first time, having a family — it was an incredible effort to come back to tennis," the coach tells PEOPLE. "Unbelievable effort. Mental effort, physical effort, so many hours to get back in shape. She would never even start that if she didn't think she was able to win a Grand Slam." He added, "That's how Serena is really exceptional. She puts the standards so high for herself, and she finds a way to match those standards, whatever she does." Daniel Pockett/Getty Images Serena Williams, Rafael Nadal Praise 'Strict' COVID Rules at Australian Open: 'Doing It Right' Though he's training two players pursuing Grand Slam titles this year — Williams and 22-year-old Stefanos Tsitsipas — the renowned coach is looking ahead to host another Ultimate Tennis Showdown, a league that started last year and uses a modified format consisting of timed quarters. "The way people consume videos has completely changed since social media, video games, sports and platforms like Amazon or Netflix have emerged," Mouratoglou said. "People watch videos that are shorter, more engaging, faster. Tennis doesn't fit those formats, so the younger generation doesn't want to consume tennis." "That's what UTS does, and that's what is extremely exciting. In a way, we [are] proposing a completely different experience of tennis," he continued. "And top players are participating. They play a shorter, faster, and more immersive tennis than what regular tennis is." DAVID GRAY/AFP via Getty Images Rafael Nadal Loses in Australian Open Quarterfinals, Won't Go for Record 21st Title One of the players who partook in the league was Tsitsipas, who Mouratoglou has trained since 2018 and is rapidly climbing the ATP ranks to be in the company of top men's players like Roger Federer, Novak Djokovic and Rafael Nadal. Though the Greek tennis player has yet to win a Grand Slam, it doesn't seem like he's far off. "He's among the two, three that clearly showed that they will be the next ones once Rafael, Roger and Novak will retire," the coach told PEOPLE. "He's extremely ambitious. He has the tennis, he has the mind. I'm sure he's going to win Grand Slams. I'm sure he can be number one, but I respect a lot of the competition that is going to be tough." Tsitsipas ended up losing to Russia's Daniil Medvedev in the Australian Open semifinal on Friday. Serbia's Novak Djokovic, currently the world ranked no. 1, edged out Medvedev and won his 18th Grand Slam title on Sunday. Osaka won the women's singles final one day prior.