BRISBANE, Australia (AP) World No. 1-ranked Ash Barty's new year has started with an upset loss to American qualifier Jennifer Brady.
The 53rd-ranked Brady, who has no WTA tournament victories, beat French Open champion Barty on her home court at Pat Rafter Arena 6-4, 7-6 (4) on Thursday.
It was a second-round match for both players but Barty had received a first-round bye. Brady had beaten wild-card entry Maria Sharapova in the first round in three sets.
It's the first time in three matches the 24-year-old Brady has defeated Barty, who was guilty of multiple unforced errors throughout the match.
Brady's baseline game was crucial to the win, swinging hard throughout with a rusty Barty unable to break the American's rhythm.
Brady won the opening set in 36 minutes, securing the only break of serve of the match in the seventh game of the set. Barty failed to get close to breaking Brady's serve throughout and couldn't force the match into a third set after a 55-minute second set.
The 23-year-old Australian remains active in the doubles at her hometown event and is in the field for next week's Adelaide International before starting her Australian Open campaign.
In later matches Thursday, defending Australian Open champion Naomi Osaka played American Sofia Kenin and two-time Wimbledon champion Petra Kvitova took on Ludmilla Samsonova.