Australian wildcard and Melbourne hopeful Olivia Rogowska is out of the 2018 Australian Open after a shock result.

Rogowska equalled her best showing at the local grand slam by moving through to the second round with a win over young compatriot Jaimee Fourlis on the opening day.

But the 26-year-old could not advance any further, upset in straight sets by teenage Ukrainian qualifier Marta Kostyuk at Margaret Court Arena on day three.

Rogowska, ranked 168th in the world, was disappointed with her performance straight sets 6-3 7-5 defeat to the 15 year old Kostyuk.

“Yeah, definitely not a good day at the office,” Rogowska said.

“I struggled today to final any rhythm, to settle down.”

Rogowska could not quite hit the mark on serve and it put her on the back foot.

She only had success on 50% of her service games, taking five of 10 games, while Kostyuk took eight of her 11 games.

Rogowska praised Kostyuk for her power and energy.

“I think my serve percentage was pretty low today,” Rogowska said.

“Credit to her, she was just firing right [back] at me. As soon as I served, like, a ball was at my feet. She did that really well today.”

It’s early in the season for Rogowska and she wants to keep fighting to improve her ranking.

Getting granted a wildcard at the Australian Open was a boon for her to gain experience at the level.

“I want to try and expose myself to that level as much as I can,” she said.

“I’m going to try and hit the WTA tour as much as I can [though] qualifying. It’s been going really well in practice. I just need to get that in matches as much as I can, shrug off this disappointment and come back firing hopefully.”