An error-strewn performance from Aryna Sabalenka saw her lose in the first round of the Adelaide International 2 tournament.
Having struggled with her serve all game, the 23-year-old star fell to a 5-7 6-1 7-5 loss at the hands of world No.93, Rebecca Peterson.
Entered as the top seed of the tournament, her struggles with serving were on show all match, with Sabalenka even opting to occasionally serve underarm.
It's a strange flaw in her game considering Sabelenka has previously thrived in her serving. She holds the record for the most aces in one match of women's Wimbledon history, when she and Karolina Pliskova served up 32 against each other back in July.
Her shock loss comes just a week after she was dumped out of the Adelaide International 1 event, where she again struggled serving with 18 double faults.
With the Australian Open just six days away from it's start date, Sabalenka was tipped to rival world No.1 Ash Barty for the Grand Slam title, but with consecutive defeats in Adelaide, doubts over her chances are starting to creep in.
Elsewhere in the tournament, third seed Coco Gauff made a statement by beating Katerina Siniakova 6-1 6-2, while Tamara Zidansek went behind to Britain's Heather Watson before rallying to win 2-6 6-2 7-6(4).
British No.1 Emma Raducanu also suffered defeat on Tuesday as she was thrashed 6-0 6-1 on her return to the court by world No 13 Elena Rybakina in the Sydney Tennis Classic.
With the women's singles draw on Thursday, both Raducanu and Sabalenka will take the next few days to recover, prepare and build up their confidence ahead of the opening matches next Monday.