Five-time Grand Slam champion Iga Swiatek showed no mercy against eighth seed Emma Navarro on Wednesday to storm into the semifinals and move closer to a maiden Australian Open title.

Second-seeded Swiatek was unstoppable in sunny conditions on Rod Laver Arena, swatting aside the American 6-1, 6-2 in one hour and 29 minutes.

The Pole has shown no signs of being affected by the doping saga hovering over her, dropping just 14 games so far in this tournament.

Having previously struggled at the Australian Open by her lofty standards, Swiatek has been on a mission as she reached the last four for the second time from seven appearances in Melbourne. She won only five games in the 2022 semifinals against Danielle Collins.

She will next face former US Open finalist Madison Keys, who came from behind to beat 28th seed Elina Svitolina in three sets.

"I think it was tougher than the score said. I wanted to stay focused until the end and keep my intensity," Swiatek said.

The 23-year-old players are separated by just 13 days in age, but their only professional meeting came in 2018, when Swiatek lost only two games.

Navarro was hoping to match her best Grand Slam result after making a stirring semifinal run at last year's US Open. Renowned for her composure, she had battled through four consecutive three-set matches, including a second-round thriller against China's Wang Xiyu.

Her task was made harder with Swiatek immediately in the groove, hitting corners with precision as consecutive backhand winners secured an early break to love. Another sublime backhand down the line helped Swiatek maintain her break advantage.

Navarro finally got on the board in the third game but was often forced to stretch every sinew as she was dragged beyond the lines. Attempts to unleash heavier groundstrokes saw unforced errors mount.

Swiatek countered by stepping forward and finishing points early, comfortably sealing the first set. Navarro fought on and earned a break point in the fifth game of the second set, but Swiatek fended off the challenge with a brilliant backhand winner to cap a lengthy rally.

That point was tinged with controversy as the ball appeared to bounce twice before Swiatek's retrieval at the net, leading to her winner. Navarro's plea for a review went unheeded, and her hopes of mounting a comeback faded quickly.