Rybakina, who has lifted the Brisbane and Abu Dhabi trophies this year, dropped serve twice at the start of the clash but she stemmed the flow of errors from her racket and won five games in a row from 4-1 down to claim the opening set.

Fernandez showed more fight in the second set, but the 2021 US Open runner-up could not prevent former Wimbledon champion Rybakina from grabbing two more breaks and powering to victory on the back of some big hitting.

"It was a difficult match. I didn't start the set well. It took me some time to get used to Leylah's ball," Rybakina said after clinching a joint tour-leading 14th win of the season.

"She plays very different. Also a lefty. I'm really happy I managed to win the first one. After that, it was a bit easier to start the second."

Up next for the Moscow-born Kazakh is a clash with Anastasia Pavlyuchenkova after the unseeded Russian reached the Doha semi-finals for the first time following a 7-5, 6-4 win over American qualifier Danielle Collins.

"Hopefully it's going to be a great match to see. We know each other very well on the court and off the court. Hopefully I can recover and show some good tennis," Rybakina added.

The top-ranked Iga Swiatek plays double Grand Slam champion Victoria Azarenka in another quarter-final on Centre Court later on Thursday, before Naomi Osaka takes on Karolina Pliskova in a clash between former world number ones.