Sabalenka digs deep to reach last 16 at Australian Open

World No. 1 Aryna Sabalenka overcame a patchy performance on Friday to defeat Anastasia Potapova on two tiebreaks in the Australian Open third round.

The four-time Grand Slam champion battled in warm conditions at Rod Laver Arena before prevailing 7-6 (4), 7-6 (7) in just over two hours.

The 27-year-old has reached the second week in Melbourne for the sixth straight year.

"She played incredible tennis. I was able to still fight for every point and I'm super happy to get this win," Sabalenka said.

The two-time Australian Open champion raced out of the blocks to gain a 2-0 lead before her normally rock solid game fell apart with a slew of unforced errors.

The 55th-ranked Potapova forced a tiebreak, but Sabalenka clinched the first set with a backhand winner down the line before unleashing a roar in celebration.

Potapova's hopes of reaching the last 16 at a Grand Slam for just the second time in her career evaporated as Sabalenka stormed to a 4-0 lead.

The match turned unexpectedly as Potapova capitalized on a sluggish Sabalenka, but squandering four set points proved costly.

Sabalenka will next play 19-year-old Canadian Victoria Mboko, who beat 14th seed Clara Tauson of Denmark 7-6 (5), 5-7, 6-3 to progress to the second week of a Grand Slam for the first time.