Iga Swiatek dropped a set for the first time in more than a month but stayed on course for the French Open title by beating ailing teenager Zheng Qinwen.
There was some doubt that the seemingly unstoppable world number one was going to extend her winning streak to 32 matches when Zheng snatched the first set despite trailing 5-2.
The 19-year-old from China was also 5-2 down in the tie-break, but reeled off five consecutive points to win it.
However, a thigh injury ultimately cost the unlucky Zheng the chance of a major upset as Swiatek won 6-7 (5) 6-0 6-2 to reach the quarter-finals.
“She’s playing amazing tennis, I’ve never had chance to play her before and I was surprised by some of her shots,” said the 20-year-old from Poland.
“Huge congrats to her. I’m pretty happy I could come back from a frustrating first set and I’m proud of myself that I’m still in the tournament.
“The quarter-final is such a stressful round so hopefully I can loosen up.”
Swiatek will face American 11th seed Jessica Pegula, who beat Irina-Camelia Begu of Romania 4-6 6-2 6-3, in the last eight.
There will definitely be a Russian in the semi-finals with Veronika Kudermetova and Daria Kasatkina to meet each other.
Banned from Wimbledon, the Russians are making hay in Paris with Kudermetova beating American 22nd seed Madison Keys and Kasatkina defeating Camila Giorgi, the 28th seed from Italy.
