Fourth seed Simona Halep has continued her impressive run at the Australian Open, downing Belgian Elise Mertens 6-4 6-4 to advance to the quarter-finals.
The two-time major winner from Romania looked to be cruising to victory, when she broke Mertens' serve twice early in the second set on Monday to take a 3-0 lead.
But the 16th-seeded Belgian - whose best Grand Slam performance was a semi-final outing on her 2018 debut at Melbourne Park - fought back to level at 4-4.
Halep broke again for 5-4 and then served out the match to love for a fourth successive straight-sets win.
Halep is the reigning Wimbledon champion, with her other major title coming at the 2018 French Open.
The Romanian star, who lost the 2018 Australian Open final to recently retired Caroline Wozniacki, is coached by Australian Darren Cahill.
Halep will play either No.28 seed Anett Kontaveit from Estonia or Poland's Iga Swiatek in the quarter-finals.
Meanwhile, Austrian Dominic Thiem is into the men's quarter-finals for the first time, after a straight-sets demolition job on Frenchman Gael Monfils.
Thiem had never passed the fourth round at Melbourne Park, but the fifth seed swept aside world No. 10 Monfils 6-2 6-4 6-4 on Monday on Rod Laver Arena.
Thiem will face the winner of Monday night's clash clash between Aussie Nick Kyrgios and world No.1 Rafael Nadal.