After the tournament was cancelled in 2020, Barty returned in 2021 and successfully defended her title.
No.1 seeds Barbora Krejcikova and Katerina Siniakova have clinched their fourth Grand Slam women's doubles title as a team.
All of Barbora Krejcikova, Madison Keys and Jessica Pegula qualified for the Australian Open quarterfinals on Sunday (January 23).
The No.6 seed from Spain defeated No.8 seed Anett Kontaveit of Estonia 6-3, 7-5 to capture her third and biggest title of the year.
Muguruza impressively fought back from a set down to defeat Barbora Krejcikova at the Akron WTA Finals Guadalajara.
The WTA Finals 2021 will close out the women's tennis season at the end of the year and so far, four of the eight spots in the tournament have been filled.
Fernandez is now the youngest woman to reach the final four in Flushing Meadows since 18-year-old Maria Sharapova did so in 2005.
The German player, who ended Novak Djokovic’s historic ‘Golden Slam’ bid, dropped just one set in Tokyo en route to the gold medal.
Ashleigh Barty, second seed Aryna Sabalenka, Ons Jabeur, and former world No 1 Karolina Pliskova reached the first quarterfinal.
After their traditional 'Middle Sunday' of rest, Wimbledon 2021 returns with with 'Manic Monday' on July 5 as the Round of 16 commences.