Tallinn Open top seed Anett Kontaveit kept her hopes of winning her home tournament alive with a 6-2 6-1 demolition of Tereza Martincova on Thursday.
The 26-year-old won five out of the final six games as she stormed to the first set, before securing her place in the quarter-finals with a superb second set in which she broke Martincova four times.
Fellow Estonian Kaia Kanepi is also through to the quarter-finals after a 7-5 7-5 victory over Ann Li.
The world number 32 found a crucial break with the opener tied at 5-5 as she took the first set, before breaking Li three times in the second to seal the win.
Eighth seed Shuai Zhang was dumped out by Donna Vekic in a 6-2 6-4 defeat, while fellow seed Jil Teichmann also saw her tournament ended as Ysaline Bonaventure beat her 7-6 (10-8) 6-3.
At the Parma Ladies Open, top seed Maria Sakkari came from a set down for the second consecutive match to overcome Maryna Zanevska and reach the semi-finals.
Zanevska sparked hopes for an upset as she broke the world number seven three times on her way to taking the opening set.
But Sakkari improved in the second to tie the match, before overcoming two breaks of serve from her Belgian opponent to win six of the last seven games and earn a 2-6 6-4 6-4 success.
Sakkari will face Danka Kovinic in the semi-finals, after the 27-year-old's 6-4 6-4 triumph over Italian Jasmine Paolini.
Irina-Camelia Begu's run of 12 consecutive wins on clay came to an end as she was defeated 6-2 7-6 (8-6) by Ana Bogdan in an all-Romanian clash.
Bogdan's opponent in the final four will be Mayar Sherif, who beat American Lauren Davis 7-6 (7-2) 6-3.