With the topic of athletes' mental health and pressure being discussed at the Olympics, Novak Djokovic said "pressure is a privilege".
The top-ranked Serb was asked how he deals with the pressure of attempting to accomplish something that no man has done before in tennis: completing a Golden Slam.
Steffi Graf in 1988 is the only tennis player to achieve the Golden Slam, winning all four Grand Slam tournaments and Olympic gold in the same calendar year.
"Pressure is a privilege, my friend," Djokovic said in answer to a reporter's question after winning both of his matches at the Ariake Tennis Park on Wednesday, beating Alejandro Davidovich Fokina of Spain to reach the quarter-finals in singles then teaming with partner Nina Stojanovic for another victory in the opening round of mixed doubles.
"Without pressure there is no professional sport," Djokovic added. "If you are aiming to be at the top of the game you better start learning how to deal with pressure and how to cope with those moments — on the court but also off the court."
Djokovic, who has already won the Australian Open, French Open and Wimbledon this year and needs the Tokyo Games title and the US Open trophy to complete a Golden Slam, said he has learned to deal with all expectations.
"All that buzz and all that noise is the thing that, I can't say I don't see it or I don't hear it, of course it's there, but I've learned, I've developed the mechanism how to deal with it in such a way that it will not impose destruction to me. It will not wear me down," Djokovic said. "I feel I have enough experience to know myself how to step on the court and play my best tennis."
Djokovic struggled more with mental pressure at the start of his career when he wasn't winning as much as long-time rivals Roger Federer and Rafael Nadal. He won the Wimbledon title this month to match Federer and Nadal with his 20th Grand Slam.
"Of course. It's normal," Djokovic said. "No one is born with those abilities. Those abilities come with time."
Tennis player Naomi Osaka and American gymnast Simone Biles are among the Olympians who have talked openly about their mental health troubles.
Djokovic's only Olympic medal was bronze in singles from his first Olympic appearances at the 2008 Beijing Games. He then lost to Juan Martin del Potro of Argentina in his next two Games: in the 2012 bronze-medal match and the first round at the 2016 Rio de Janeiro Games.
"Rio was (a) very tough loss for me," Djokovic said. "I came into Rio as also a big favourite, winning four out of last five Grand Slams, No.1 in the world. So I know that feeling; it's kind of a similar feeling now. But I'm a more experienced player; I know mentally what I need to do and how to work things around on and off the court in order to feel the best that I possible can feel."
Twenty athletes, including 10 from Nigeria, will not be allowed to participate in track and field at the Olympics because they did not meet anti-doping testing requirements in the lead-up to the Games.
The Athletics Integrity Unit, which runs the anti-doping program for the sport, requires athletes from countries categorised as "high risk" because of deficiencies in their testing programs to be given three no-notice, out-of-competition tests in the 10 months leading to a major event.
Each of the seven so-called "Category A" countries had at least one athlete banned from the Games. The countries are Belarus, Bahrain, Ethiopia, Kenya, Morocco, Nigeria and Ukraine. AIU does not release the names of the banned athletes.
Kenya had previously announced that two of its runners, who are among the 20 mentioned in the AIU release, did not meet the qualifications.
Their removal made room on the squad for 1,500-metre world champion Timothy Cheruiyot, who has the world's best time this year but surprisingly finished fourth at the country's Olympic trials.
AIU chair David Howman said there have been improvements in the "Category A" countries' testing programs "but there remains a long way to go in some circumstances."
Australia has already won four gold medals in the Tokyo Olympics pool and more are on offer on Day 6 of the Games.
Jack McLoughlin - the 400m silver medallist - swims the 800m final, though will need to lift are qualifying sixth.
Zac Stubblety-Cook has qualified fastest for the men's 200m breaststroke final and will hope to join Ariarne Titmus and Kaylee McKeown as individual gold medallists for Australia in Tokyo.
Brianna Throssell swims the 200m butterfly final, having qualified sixth fastest.
Kyle Chalmers will defend his 100m freestyle title in the blue riband men's final, needing to fire up after qualifying sixth for the decider against the likes of USA's Caeleb Dressel and ROC's Kliment Kolesnikov.
And the Australian women's 4x200m freestyle relay team looks a good thing for gold, having qualified fastest for the final. Incredibly, none of the heat swimmers look likely to swim the decider, such is Australia's depth.
Mollie O'Callaghan, Meg Harris, Brianna Throssell and Tamsin Cook clocked 7:44.61 to easily win their heat and put Australia through. Yet Titmus, Emma McKeon, Madi Wilson and Leah Neale seems almost certain to be the Australian team for the final.
The heat swimmers are still awarded medals.