Top seed Anastasia Pavlyuchenkova only had a light workout as she progressed to the quarter-finals of the Baku Cup after Kateryna Bondarenko retired early on in their second-round match.
Bondarenko withdrew due to injury after 13 minutes with Pavlyuchenkova leading 3-0.
It means the Russian number-one seed will face either Kristen Flipkens or Vitala Diatchenko in the last eight.
Russia's Margarita Gasparyan also progressed to the quarter-finals with a 6-4 6-4 win over China's Yang Zhaoxuan and Donna Vekic booked her place with a 6-4 0-6 6-3 victory against Zhu Lin.
Alexandra Panova moved into the quarter-finals thanks to her 7-6 (7/4) 6-2 win over Andrea Hlavackova.
Meanwhile, second seed Karin Knapp made comfortable progress into the second round with a straight sets win over Stefanie Voegele.
Italian Knapp came through 6-1 6-4 in an hour to line up a match with Anett Kontaveit.
Evgeniya Rodina was handed a pass through to the second round when opponent Danka Kovinic retired when her opponent was leading 6-0 2-0.
Source: PA
