Petra Martic and Anett Kontaveit battled into the Palermo Ladies Open quarter-finals, while Dayana Yastremska cruised through.
Martic, the top seed at the WTA International event that marks the return of the Tour amid the coronavirus pandemic, overcame Liudmila Samsonova 5-7 6-4 6-2.
Croatian Martic, the world number 15, needed two and a half hours to get past the qualifier in Italy on Thursday.
She will face Aliaksandra Sasnovich in the last eight.
Kontaveit was also pushed before recording a 3-6 6-2 6-2 victory over Laura Siegemund.
Yastremska and Camila Giorgi will meet in a quarter-final after respective wins over Oceane Dodin and Kaja Juvan.
Talented Ukrainian seventh seed Yastremska was too good for Dodin 6-2 6-4, while Giorgi beat Juvan 3-6 6-2 6-4.