It's Serena vs. Osaka and David vs. Goliath at the Australian Open

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The Australian Open is getting really interesting

Two big quarter-final upsets rocked the year's first tennis Grand Slam last night and this morning. First, women's No. 1 Ash Barty lost 1-6, 6-3, 6-2 to 25th-seeded Karolina Muchova, ending the Australian's hopes of winning her country's major for the first time. Then it was Rafael Nadal's turn to build up a big lead before falling apart. The No. 2 seed lost 3-6, 2-6, 7-6 (4), 6-4, 7-5 to No. 5 Stefanos Tsitsipas, ruining Nadal's chance to take sole possession of the all-time record for men's Grand Slam singles titles. He remains tied with Roger Federer at 20. Read more about the Nadal and Barty upsets and watch highlights here.

Three of the four semifinals take place tonight or early tomorrow morning in Canadian time zones — including the two most interesting. Let's take a look at those:

Serena Williams vs. Naomi Osaka (10 p.m. ET)

They saved the best for first. The opening semifinal is a showdown between the two biggest stars in the women's draw — and the two highest-earning female athletes in the world.

Serena needs no introduction. She's one of the greatest and most glamorous athletes of all time and has won 23 Grand Slam singles titles. But, at 39, she's running out of daylight to grab the one additional Slam title she needs to match Margaret Court's all-time record. It's been four full years since Williams last won one.

There will never be anyone else quite like Serena, but the 23-year-old Osaka is the closest thing right now to a natural successor. Like Serena, she's hip, popular with fans around the world, plays a powerful game and stands out as a star of colour in a mostly white sport. Osaka already has an Australian and two U.S. Open titles under her belt. She's won three of the last eight Slams. No other woman has won more than one in that span.

The winner of the Osaka-Williams match will be favoured to beat whoever emerges from the other semifinal. That match also takes place tonight and it pits Muchova against 22nd-seeded American Jennifer Brady.

Aslan Karatsev vs. Novak Djokovic (3:30 a.m. ET)

David vs. Goliath. Djokovic is the world No. 1 and an eight-time Australian Open champion. He's won 17 Grand Slams, 81 ATP Tour titles and earned nearly $146 million US in prize money in his career. He's one of the greatest tennis players ever.

Karatsev is essentially a minor leaguer. The 27-year-old Russian is ranked 114th in the world and this is his first Grand Slam. In fact, he's played only 13 matches at the ATP Tour level (going 3-10) and his career earnings are $618,000 — less than a quarter of what Djokovic made just for winning the Aussie Open last year. Karatsev has spent the bulk of his career grinding out a living in tennis' bush leagues — the ITF and Challenger Tours. He was ranked 253rd when tennis returned from its five-month pandemic pause last year.

But something has clicked for him since then. Karatsev closed out 2020 by going 19-2 and winning two titles on the Challenger Tour, which is the top minor-league circuit. When he moved up to a few low-stakes ATP Tour events, he went a non-terrible 2-3 in his main-draw matches.

In 2021, Karatsev is undefeated. He won three consecutive Australian Open qualifying matches to reach the main draw of a Slam for the first time in 10 attempts, and has proceeded to rattle off five impressive wins. In his second-round match he nearly pitched a shutout, losing only one game. Then he destroyed eighth-seeded Diego Schwartzman in straight sets before rallying from two sets down to beat 20th-seeded Canadian Felix Auger-Aliassime. A pretty easy four-set win over No. 18 Grigor Dimitrov made Karatsev the first man in the Open Era (since 1968) to reach the semifinals in his Grand Slam debut.

Even if Karatsev loses to Djokovic (oddsmakers have him as a 9/1 underdog), he's projected to break into the top 50 when the new world rankings are released. If he pulls off the upset he'll bust into the top 30 and play for the Aussie Open title against either Tsitsipas or No. 4 seed Daniil Medvedev. Their semifinal is Friday at 3:30 a.m. ET.

Quickly…

Bianca Andreescu won again. She survived a deciding-set tiebreaker vs. Irina-Camelia Begu to reach the semifinals of the Phillip Island Trophy — an event for players who either didn't qualify for the Australian Open or got eliminated early. Since being ousted in the second round of the Aussie, which was her first tournament in more than 15 months, Andreescu has beaten the world's 85th, 83rd and 74th-ranked players at the Phillip Island. The 20-year-old Canadian, who is still ranked ninth despite her long layoff, faces 50th-ranked Marie Bouzkova in the semis. Read more about Andreescu's win over Begu and watch highlights here.

The Canadian Olympic Committee is opposed to taking the 2022 Winter Games away from Beijing. Several Canadian politicians have called for China to be stripped of the Games, including NDP Leader Jagmeet Singh and Conservative Leader Erin O'Toole. Citing China's treatment of the Uighurs, its actions in Hong Kong and its ongoing detention of Canadian citizens Michael Kovrig and Michael Spavor, O'Toole said yesterday that if the Olympics can't be moved and China doesn't change its "conduct," Canada should consider a boycott. The COC had already said it's opposed to a boycott because it believes they don't work, and the organization's CEO added last night that he's also against relocating the '22 Olympics. "We believe that moving the Games less than a year out would be next to impossible," David Shoemaker said in a statement. "Organizing an Olympic Games is an incredibly complex undertaking that typically takes more than seven years to do. As is the case for any Olympic Games, the COC will focus on its role of preparing Team Canada for success and promoting the Olympic values at home and abroad." Read more about the 2022 relocation/boycott debate here.

The Canadian men's water polo team advanced to the next round at its last-chance Olympic qualifier. Brazil took care of that today by losing to Georgia to finish 0-4 in the round robin. That, coupled with Turkey's disqualification from the tournament because of a coronavirus outbreak, guarantees Canada will place no worse than fourth in its group — good enough for a spot in the quarter-finals. The final three spots in the Olympic men's tournament are up for grabs at this qualifier in the Netherlands. Two will go to the winners of the semifinals, and the other to the winner of the third-place game. Canada can earn a more favourable matchup in the quarter-finals by beating Greece in its round-robin finale on Thursday. The game starts at 8:30 a.m. ET and you can watch it live here.

Also coming up on CBC Sports

Alpine skiing world championships: Coming off her victory Monday in the combined event, Mikaela Shiffrin goes for her second gold medal of the meet in the women's giant slalom. The American star has never won a world title in this discipline, but Shiffrin reached the GS podium at the last two worlds and is the reigning Olympic champ. She also has 12 World Cup wins in the GS — making it her second-best discipline, behind the slalom. Watch both runs live Thursday at 4 a.m. ET and 7:30 a.m. ET here.

Snowboard cross: Watch this week's men's and women's World Cup races in Austria live Thursday from 5:30-7 a.m. ET on CBCSports.ca and the CBC Sports app.

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