Ruthless Halep storms into Aussie Open quarter-finals

Melbourne: Two-time Grand Slam champion Simona Halep surged into the quarter-finals of the Australian Open on Monday with a straight-sets victory over 16th seed Elise Mertens.

The fourth seed won 6-4 6-4 and plays Estonian 28th seed Anett Kontaveit or unseeded Polish teenager Iga Swiatek in the last eight in Melbourne.

Former world number one Halep, beaten in the 2018 final by Caroline Wozniacki, has not dropped a set in four matches in Melbourne and the Romanian looks in ominous form.

With her win, the 28-year-old will rise from third to second in the rankings.

"I had to calm myself down because when I get a little bit nervous I get crazy on court so I had to stay cool, to get energy from the box and play without looking back," she said, after some anxious moments in the second set.

After top seed Ashleigh Barty, Halep -- last year's Wimbledon champion and a former French Open winner -- is the highest remaining seed left in the draw.

Second seed Karolina Pliskova, holder and third seed Naomi Osaka, and history-chasing Serena Williams were among six top-10 seeds who lost in the third round.

Halep defeated Belgium's Mertens in two of their three previous meetings, including in the last 16 of the French Open in 2018, when she went on to win the title.

But Mertens prevailed the last time they met when she came from a set down in the final in Doha last year.

Halep drew first blood at a sunny Rod Laver Arena when she broke Mertens at the fourth break-point opportunity and consolidated for a 3-1 lead.

The 24-year-old Mertens, whose best performance at a Grand Slam came in reaching the Australian Open semi-finals in 2018, broke back and then stubbornly held serve for 4-3.

But Halep broke again for 5-4 and converted the fourth set point when Mertens put a forehand into the net.

The Romanian began the second set with intent, breaking for another early lead, but Mertens would not go quietly, breaking back as she piled on the pressure.

The ninth game proved pivotal, as Halep finally got the break at the fifth opportunity before serving out the match.

Meanwhile, Two-time Grand Slam champion Garbine Muguruza underlined her return to form as she beat ninth seed Kiki Bertens in 68 minutes to reach the Australian Open quarter-finals on Monday.

The unseeded former world number one won 6-3 6-3 on Rod Laver Arena and faces German 17th seed Angelique Kerber or 30th seed Anastasia Pavlyuchenkova of Russia in the last eight.

Just three of the top 10 seeds remain -- top seed Ashleigh Barty and seventh seed Petra Kvitova meet in the quarter-finals.

The other is Simona Halep, the fourth seed, who plays Estonian 28th seed Anett Kontaveit.

The 26-year-old Muguruza reunited with Conchita Martinez, her fellow Spaniard and the 1994 Wimbledon champion, at the start of the year in the hope of reviving her failing career.

Muguruza, who has suffered a barren 18 months, said she was enjoying having Martinez on her coaching team.

"When you talk to another player you don't have to put too many words, you right away understand each other," she said.

As part of her reboot, Muguruza spent a few days in the off-season climbing Mount Kilimanjaro to clear her mind of tennis.

Muguruza ended 2019 ranked 36 in the world, the first time since 2014 that she had finished the year outside the top 20.

But she has flickered back to life in 2020, reaching the semi-finals in Shenzhen at the start of the year before pulling out of Hobart in the quarter-finals with a virus.

"First day I was not feeling good at all (in Melbourne) but every day it's improving," she said.

Muguruza emphatically won the first set in 30 minutes against a shell-shocked Bertens.

She took the momentum into the second set, breaking for a quick 1-0 lead, only to be broken back immediately.

The resurgent Spaniard broke Bertens once more for 3-2 and comfortably held for 4-2.

Muguruza broke again for a 5-3 lead and put Bertens under pressure with some powerful groundstrokes from the back of the court.

She failed to put Bertens away on the first match point but sealed the win with another big forehand, this one pinging down the line.