Defending champion Petra Kvitova and former world No.1 Victoria Azarenka have both bowed out of the Qatar Open through injury, on a day in which a host of favoured seeds advanced in Doha.

Kvitova — the winner of the 2018 and 2021 editions of the tournament — was unable to finish her match against Elise Mertens, later tweeting that an injury to her left wrist had flared up during the second set.

Mertens, the 2019 champion, was unable to serve out the opening set at 5-4 after committing consecutive double faults, but made no mistake with her second opportunity to close it out 7-5.

Kvitova had held for 2-1 in the second set when the Czech called for the trainer and opted to retire.

Mertens, the 16th seed, will face St Petersburg champion Anett Kontaveit, the fourth seed, in the round of 16.

Azarenka announced her withdrawal from the WTA 1000 event through injury, suffering pain in her left hip before her scheduled second round match with American Madison Brengle.

Meanwhile, a host of the tournament’s favoured seeds had better fortune on a day of few surprises.

World No.2 and top seed Aryna Sabalenka breezed past France’s Alize Cornet 6-2 6-2.

World No.3 Barbora Krejcikova made light work of Magda Linette 6-1 6-3 and will face former French Open champion Jelena Ostapenko next, the Latvian accounting for Amanda Anisimova 6-3 4-6 6-4.

Paula Badosa saw off Clara Tauson 6-1 6-2 to set up a showdown with 17-year-old American Cori Gauff, who defeated Caroline Garcia 6-2 7-6 (7-3).

There were three-set wins for top-10 players Iga Swiatek and Ons Jabeur while sixth-seeded Maria Sakkari accounted for Ann Li 6-3 6-3 to round out the day’s action.