Rafael Nadal continues impressive comeback as he marches on at Brisbane Classic

The 22-time grand slam champion played his first match for nearly a year following a hip injury in the opening round against Dominic Thiem and built on that performance by seeing off Australian Kubler 6-1 6-2.

Nadal, who shrugged off a time violation in the second set for taking too long to change his clothes, told reporters in Brisbane: "It has been a positive match, without a doubt.

"I think the first five games of the match have been at a very positive level of tennis, doing almost everything the right way. Most of the time I have been playing well, doing the things that I need to do. I'm happy for the victory. Of course, it's important for me."

The Spaniard will next face another Australian in Jordan Thompson.

Second seed Grigor Dimitrov, who defeated Andy Murray in round one, also eased into the quarter-finals with a 6-1 6-2 win over Daniel Altmaier.

In the women's event, top seeds Aryna Sabalenka and Elena Rybakina were both in fine form, losing just a game apiece.

Sabalenka, who defeated Rybakina to win her maiden grand slam title at the Australian Open 12 months ago, saw off Zhu Lin 6-1 6-0 while Rybakina beat 13th seed Elise Mertens by the same scoreline.

Russian 16-year-old Mirra Andreeva, meanwhile, is also through to the last eight after an almost-as-convincing 6-1 6-1 victory over Arina Rodionova and will next face another teenager in Czech Linda Noskova.

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