Japan's Osaka was playing at the Foro Italico for the first time in three years after taking a break from the tour to have her first child and is ranked at 173 in the world.

The furthest she has gone in any tournament so far this season was her run to the quarter-finals in Doha, which she could not replicate in the Italian capital.

However, it was a positive tournament for Osaka, who has never won a title on clay but beat a top-20 ranked player on the surface for the first time, against Marta Kostyuk in the second round on Thursday.

China's Zheng breezed past Osaka in one hour and 24 minutes to set up a last-eight clash with either Paula Badosa or third seed Coco Gauff.

Later Iga Swiatek continues her bid for a third Rome title against Angelique Kerber, while Australian Open champion Aryna Sabalenka will face Elina Svitolina for the first time since their handshake row at last year's French Open.

World number one Swiatek is yet to drop a set and is red-hot favourite to make the quarter-finals past unseeded German Kerber, who at 331 is the lowest-ranked player ever to reach the last 16 in the Italian capital.

Three-time French Open champion Swiatek arrived in Rome off the back of a thrilling triumph in Madrid, her third WTA 1000 title of the season after also winning at Indian Wells and Doha.

Belarusian second seed Sabalenka was accused by Ukraine's Svitolina of inflaming tensions surrounding the Russia-Ukraine war after the Roland Garros quarter-finals in 2023.

Sabalenka waited at the net for a handshake after beating Svitolina, even though Svitolina had already insisted she was not going to offer one, as all Ukraine players refused to shake hands with Russian and Belarusian rivals in protest at the ongoing war.