World No 2 Karolina Pliskova joined the list of seeds to exit the Australian Open at the third round after a straight-sets defeat to Russian Anastasia Pavlyuchenkova.

Pliskova suffered a 7-6 (7-4) 7-6 (7-3) loss against the 30th seed as the Czech became the highest seed to drop out of the women’s draw, a day after defending champion Naomi Osaka and 23-time Grand Slam singles winner Serena Williams were also knocked out.

Pavlyuchenkova, who had lost all six of her previous encounters against Pliskova, had a 4-1 lead in the first set and a 2-0 lead in the second before winning the key points in the tiebreaks to clinch victory in two hours and 25 minutes.

Anastasia Pavlyuchenkova won two junior Grand Slam titles, including at the Australian Open in 2006 Anastasia Pavlyuchenkova won two junior Grand Slam titles, including at the Australian Open in 2006 Anastasia Pavlyuchenkova won two junior Grand Slam titles, including at the Australian Open in 2006

“It hasn’t sunk in yet. I’m still in the match and focusing on the next point,” Pavlyuchenkova said.

“I was thinking that if I take one or two games on her serve that would be amazing because she is the ace queen on the tour so that was my goal, so I was focusing on returning well.”

The 28-year-old will next meet three-time Grand Slam champion Angelique Kerber in the fourth round after the German defeated Italy’s Camila Giorgi 6-2 6-7 (4-7) 6-3.

Wimbledon champion Simona Halep delivered an impressive performance to avoid any upset as she beat Kazakhstan’s Yulia Putintseva 6-1 6-4.

Simona Halep is yet to lose a set as she targets a third Grand Slam title Simona Halep is yet to lose a set as she targets a third Grand Slam title Simona Halep is yet to lose a set as she targets a third Grand Slam title

Halep broke each of Putintseva’s service games in the first set before the Romanian fourth seed faced sterner resistance in the second, eventually securing victory when Putintseva netted a slice.

The 2018 Australian Open runner-up will next face 16th seed Elise Mertens after the Belgian defeated 20-year-old American Catherine Bellis 6-1 6-7 (5-7) 6-0.

Former world No 1 Garbine Muguruza easily overcame fifth seed Elina Svitolina 6-1 6-2 to reach the fourth round.

Garbine Muguruza marched into the fourth round with an impressive win Garbine Muguruza marched into the fourth round with an impressive win Garbine Muguruza marched into the fourth round with an impressive win

The 26-year-old is a two-time Grand Slam winner but entered the tournament unseeded after struggling in the past couple of seasons.

Muguruza broke the Ukrainian four times and saved both of the break points she faced as she set up a meeting with seed Kiki Bertens, who defeated Zarina Diyas 6-2 7-6 (7-3) to reach the fourth round for the first time.

Swiss sixth seed Belinda Bencic suffered a 6-0 6-1 defeat against Estonia’s Anett Kontaveit in 49 minutes.

Kontaveit, the 28th seed, won the first nine games as she outplayed last year’s US Open semi-finalist.