Katie Volynets has scored the most significant win of her career with her upset defeat of world number nine Veronika Kudermetova, becoming the first American qualifier to reach the Australian Open women’s singles third round in 30 years.

The 21-year-old — who is ranked 113 in the world — matched the feat of US great Lindsay Davenport, who made the third round in 1993, seven years before she claimed the women’s singles championship.

“I literally have the chills because the fans here are just incredible,” said Volnyets, who defeated Russian Kudermetova 6-4, 2-6, 6-2 on Margaret Court Arena.

“I’ve never played in a stadium this packed and with that many people keeping the energy up for me. It was awesome.”

Volynets is making only her sixth main-draw appearance in a major.

She will next meet either China’s Zhang Shuai or Croatian Petra Martic for a place in the fourth round.

Earlier, Aryna Sabalenka extended her winning streak to six matches by beating American Shelby Rogers 6-3, 6-1 on Rod Laver Arena.

The fifth-seeded Belarusian — who began the year by winning the first Adelaide International tournament — trailed Rogers 3-1 early in the match but won five straight games to take the opening set and then eased through the second.

“I expected a great level from her today, that’s why I stayed focused from the beginning to the end,” Sabalenka said.

Sabalenka will next play 26th-seeded Elise Mertens after the Belgian got past Lauren Davis of the US, 6-4, 6-3.

Another American bowed out of the tournament, with Taylor Townsend defeated by 19th seed Ekaterina Alexandrova of Russia, 1-6, 6-2, 6-3.

On the men’s side, British number 25 seed Dan Evans was an early winner on day four, beating Jeremy Chardy of France 6-4, 6-4, 6-1 to reach the last 32 for the third successive year.