Serena Williams, Novak Djokovic, Naomi Osaka, and Dominic Thiem Advance to Third Round of Australian Open

Rick Rycroft/AP/Shutterstock; DAVE HUNT/EPA-EFE/Shutterstock (2); Jason Heidrich/Icon Sportswire via Getty From L to R: Serena Williams, Novak Djokovic, Naomi Osaka and Dominic Thiem

Some of the most talked-about athletes in this year's 2021 Australian Open has secured spots in the tournament's third round.

Serena Williams, Novak Djokovic, Naomi Osaka and Dominic Thiem all advanced on Wednesday, with Williams, 39, beating Serbia's Nina Stojanovic 6-3, 6-0.

"I wasn't thinking so much in the second set as I was in the first,'' said Williams after the match, according to ESPN. "I kind of just let go and see what happened.''

Playing for just over an hour and a half, Thiem, 27, clinched a victory over Dominik Koepfer from Germany, with sets going 6-4, 6-0, 6-2.

The 27-year-old called his face-off "a super good match," reported the ATP, praising his opponent for being "on fire at the beginning."

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Mackenzie Sweetnam/Getty; Jason Heidrich/Icon Sportswire via Getty Serena Williams (L); Naomi Osaka

BRANDON MALONE/AFP via Getty; Rick Rycroft/AP/Shutterstock Dominic Thiem (L); Novak Djokovic

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"The conditions were, I think, the hottest day since we [arrived] in Australia, so I had to get used to that," he added. "[I] had to overcome some complicated situations. I think I saved two break points in the sixth game, then I broke him after [a] long game for [a] 4-3 [lead]. After that I played more freely, especially after the first set, [when] everything started to work."

Osaka's win came over French player Caroline Garcia, with the 23-year-old saying after the match, according to ESPN, "It felt great; I haven't played a night match in a long time."

"Staying focused throughout the entire match, it's hard to play opponents like her because you never know what she is going to do or how hard she is going to hit," she added.

Following his 6-3, 6-7(3), 7-6, 6-3 triumph against American Frances Tiafoe, Djokovic, 33, captioned a celebratory Instagram photo, "What a battle today, @bigfoe1998 big respect bro. R3 let's gooo!!! 💪🏼🎾🎾🎾 #Idemooo #AusOpen @australianopen."

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Ahead of the Australian Open, Osaka — who previously won the Australian Open in 2019 — chatted with PEOPLE about having used the offseason to prepare for the Grand Slam tournament.

"I've had a really productive off season training so I'm looking forward to seeing where my level is at in Australia," the tennis champ said. "I love the people and the culture in Australia, so it's a really fun time of year."

As the coronavirus pandemic continues around the world and many people's lives have been disrupted as a result, Osaka sees how lucky she is to get to continue to play tennis.

"It's been such a difficult time for so many people," the athlete told PEOPLE. "I'm grateful to have been kept busy and able to work. Not everyone has been so fortunate."