World number one Aryna Sabalenka began her Australian Open title defence with a commanding 6-3, 6-2 victory over Sloane Stephens on Sunday.
The Belarusian is chasing a rare third consecutive title at Melbourne Park.
Despite a shaky start, Sabalenka, 26, overcame a brief comeback from the 2017 US Open champion, who broke back twice in the first set.
Sabalenka responded with renewed aggression, taking the opener in 38 minutes.
The second set saw the top seed dominate, breaking Stephens twice to seal the match in just over an hour.
“It’s always tough against her,” Sabalenka said. “I didn’t play my best, but I’m happy to get through in straight sets.”
Sabalenka, who won the Brisbane International last week, aims to join legends like Martina Hingis and Steffi Graf by achieving a Melbourne three-peat.
She will face Spain’s Jessica Bouzas Maneiro in the next round.