Australian Open 2021: Serena Williams stormed into quarter-finals after victory over Aryna Sabalenka

Serena Williams stormed into the quarter-finals of the Australian Open on Sunday with a gritty 6-4 2-6 6-4 victory over Belarusian Aryna Sabalenka.

The match was a big test for Williams, who was up against one of the few players on the women's tour capable of matching her power from behind the baseline.

"I'm happy to get through that one," Williams said in an on-court interview. "It wasn't easy and I knew it wasn't going to be easy. She was teeing off on every shot.

"Even the games that I lost were super close, one shot here and one shot there, and I just felt like, 'Serena you've got this, you've just got to keep going.'"

Sisterly love @Venuseswilliams was in the crowd to cheer on @serenawilliams as she made her way into the quarterfinals #AusOpen | #AO2021 pic.twitter.com/fTsfLxGg1m

— #AusOpen (@AustralianOpen) February 14, 2021

The players went toe-to-toe in an even first set until Williams pounced late to break Sabalenka for the first time and take a 1-0 lead.

The roles were reversed at the start of the second, however, with Sabalenka breaking Williams in her first two service games.

The American, who is chasing a record-equalling 24th Grand Slam title, clawed a break back but was powerless in the face of Sabalenka's onslaught as the seventh seed broke once more for a 4-1 lead before sending the match into a decider.

"I lost the second set but the games were so close so I just tried to stay in there," Williams added.

.@serenawilliams fights on! 

Serena defeats a gallant Sabalenka 6-4 2-6 6-4 in one of the most intense matches of the tournament  #AusOpen | #AO2021 pic.twitter.com/lvZBwD3ntJ

— #AusOpen (@AustralianOpen) February 14, 2021

With the pressure ramped up in the third, it was Sabalenka who blinked first, making several errors on serve to hand Williams a 3-1 lead.

The Belarusian broke back and then levelled the set at 4-4 with a hold to love but the pressure finally told Sabalenka serving to stay in the match trailing 5-4.

Sabalenka double-faulted to give Williams a 15-30 lead and netted a forehand to hand her two match points, conceding the match by sending a forehand long.