MELBOURNE, Australia - No.4 seed Simona Halep used a mid-match swing of six straight games, and a late push to get over the line, to put away former semifinalist Elise Mertens and reach the quarterfinals of the Australian Open, 6-4, 6-4.

The World No.3 withstood a stern effort from the Belgian No.16 seed, who defeated her in the pair's last meeting to win the Qatar Total Open in Doha last February, but nonetheless advanced to the quarterfinals Down Under for the fourth time in her career. 

"I had in my head she came back in that match, and I have just to pay attention on every ball, not giving up at all, because she can come back strong," Halep said after the match.

"Mentally, I think I did a great job today at 4-All with those break points, game points. But in the end, I got the game and then I served very well the last game. I feel like I played a better match than all the matches since I'm here.

"I feel happy about that, and I'm trying just to stay focused. I like how I feel."

Through the first seven games, where Mertens rallied from 3-1 down to hold a 4-3 lead, the Belgian was the clear aggressor, striking 16 winners to Halep's six, and 16 unforced errors to Halep's three.

Nonetheless, the reigning Wimbledon champion found another gear in the middle of the match, and won six straight games en route to building a 6-4, 3-0 lead.

Though she'd lose a double-break lead in the second set as Mertens continued to show the form that took her to the final four in Melbourne two years ago, Halep secured the decisive service break at 4-4 -- on her fifth break point -- and held serve to love to win the match.

Halep recorded 21 winners to just eight unforced errors in a masterful counterpunching effort that she needed to counteract the Belgian's total of 36 winners and 38 unforced errors. 

To reach the semifinals for the second time in her career, and first since finishing runner-up at the 2018 tournament, Halep will next have to overcome either No.28 seed Anett Kontaveit or Polish teenager Iga Swiatek. 

"We [Halep and Swiatek] played together in French Open. It was good match for me, but definitely here is going to be different. I'll be ready. She's young. She has nothing to lose. Actually, I have nothing to lose, the same," the Romanian said.

"I'm just going there and do my job, because I really feel good. I feel prepared to face her.

"Kontaveit, I don't know if we played together. Probably once. She's strong. I'm here just to face any challenge I have. So I'm not thinking negative about the game. I just want to go there and to give my best. This is everything I have in my mind."

Halep holds off Mertens to return to Australian Open quarterfinals

2020 Australian Open