The first Grand Slam of the season is behind us, and with it, we saw a good amount of movement in the Monday’s latest rankings. Naomi Osaka took home the Australian Open title, her fourth career Grand Slam championship. She moved to No.2 in the rankings, overtaking Simona Halep. Osaka now trails only WTA World No.1 Ashleigh Barty, who extended her stay to 57 consecutive weeks at No. 1 (64 total weeks). 

Here are some of this week's other key ranking movers:

Serena returns to Top 10

After falling out of the WTA Top 10 in the year-end rankings, Serena Williams moved up to No. 7 (from No.11) following her semifinal run at the Australian Open.   

Sabalenka sits atop WTA doubles rankings

With a rankings resume that includes two Grand Slams - 2021 Australian Open and 2019 US Open - along with two WTA 1000s - 2019 Indian Wells and 2019 Miami - Aryna Sabalenka became the 44th player in WTA history to ascend to the World No.1 Doubles Rankings.

“I am truly honored to become the new WTA World No.1 in doubles,” Sabalenka said. “I want to thank my coach and everyone in my team, as well as my amazing partner Elise – they have all been incredible and I couldn’t have done this without them. I will remember this day for the rest of my life.”

Sabalenka is the first player in the past seven years to own the WTA Doubles No.1 ranking, while also being ranked in the Top 10 in singles. The last was Sara Errani, who on Feb. 10, 2014, was ranked No.1 in doubles and No.7 in singles.

Sabalenka has played nearly exclusively with partner Elise Mertens since 2019. This year’s Australian Open title pushed Sabalenka to No.1 and Mertens to No.2. The Belgian trails Sabalenka by 85 points due to her withdrawal at the 2020 Western & Southern Open. Mertens earned 105 points at that event, while Sabalenka picked up 190 points.

Brady reaches career-high

American Jennifer Brady jumped 11 spots in the rankings following her run to the Australian Open final to a career-high No.13.  Brady’s climb positions her as the No.3-ranked American behind only Williams and Sofia Kenin.

Kasatkina jumps after title run

After a second-round exit at the Australian Open, Daria Kasatkina maximized her stay in Melbourne by capturing the Phillip Island Trophy title, a WTA 250 tournament. The tournament featured a 56-player draw staged during the second week of the Australian Open at Melbourne Park. The unseeded Kasatkina defeated four seeds en route to winning the title, including wins over fellow Russian and No.7 seed Anasatsia Pavlyuchenkova (R16), No.4 seed Petra Martic (QF) and No.8 seed Danielle Collins (SF), before No.13 seed Marie Bouzkova stopped her in the championship match. The title pushes Kasatkina up 18 spots up the rankings, from No.75 to No.57.

2021 Phillip Island Trophy Highlights: Kasatkina bests Bouzkova for the title

Other notable rankings movement

Jessica Pegula (USA), +18 (No.61 to 43)

Hsieh Su-Wei (TPE), +21 (No.71 to 50)

Kaja Juvan (SVN), +13 (No.104 to 91)

Mayar Sherif (EGY), +17 (No.131 to 114)

Rebecca Marino (CAN), +103 (No.317 to 214)

Daria Gavrilova (AUS), +77 (387 to 310)

WTA rankings odds & ends

This week’s Top 100 features players from 31 different nations and regions with the United States leading with 18 players. The Czech Republic (9), Russia (8) and Romania (5) follow.

The average age of this week’s Top 100 is 26.36 years old with Venus Williams (40 years, 250 days, at No.76) being the oldest and Coco Gauff (16 years, 346 days, at No.52) the youngest.