Australian No.1 Ashleigh Barty has progressed through to the Sydney International semi-finals after defeating Belgian Elise Mertens in straight sets.
Ashleigh Barty has continued her sizzling summer form by surging into the final four of the Sydney International with another win over a higher-ranked opponent.
Currently ranked 15th in the world ahead of next week's Australian Open, Barty broke 12th-ranked Elise Mertens six times on her way to an emphatic 6-3 6-3 victory on Thursday.
It came just a day after toppling world No.1 Simona Halep, however the Australian No.1 put no pressure on herself to prove the victory was no fluke against the Belgian.
"It was important, but I think it wasn't the end of the world, to be honest," Barty said.
"I knew I had to come out and play a solid match today.
"Elise has had an amazing year. I knew it was going to be very tough and I was going to have to hit a lot of balls. I'm really happy with the way I was able to get in and out of games today."
The 22-year-old showed signs of frustrations early in the second set when she blew a handful of looks at Mertens' serve, but eventually broke through to advance into the semi-finals.
"It was important to try and get ahead in games today," Barty said.
"Elise is a great front-runner. I knew I had to try and take control of those first two or three points in games to give myself a chance.
"One sloppy game from me on serve in the second set was probably the only blemish."
The top-ranked Australian woman will now play world No.9 Kiki Bertens in Friday's semi-final, after the Dutch ace comfortably outed qualifier Yulia Putintseva 6-2 6-2.
Barty hasn't dropped a set in Sydney, and her only loss this year was to world No.2 Angelique Kerber in last week's Hopman Cup.
Kerber also beat her in the Sydney final last year, but won't stand in her way in 2019 after she was toppled 6-4 6-1 by world No.8 Petra Kvitova on Thursday night.
"I feel like I have played what, now six really good singles matches," Barty said.
"I feel like there haven't been too many times where I have felt uncomfortable on the court.
"I've felt like I've been in control of most of them, which is really pleasing, and putting myself in the position towards the business end of the tournament, which is what you want to do."
Meanwhile, Kvitova will face Aliaksandra Sasnovich in the other semi-final after the Belarusian's impressive summer continued with a straight-sets win over Timea Bacsinszky.
The world No.33-ranked Sasnovich, who made it to the quarter-finals last week in Brisbane, was in control most of the way before prevailing 6-3 6-3 over her Swiss opponent.