Rafael Nadal fought back from two sets down against Daniil Medvedev to win the Australian Open finalRafael Nadal registered the best start to a season in his career as he breezed past Stefan Kozlov to reach the Mexican Open quarter-finals.
The Australian Open champion extended his unbeaten run to 12 matches with a 6-0 6-3 win over American Kozlov.
Nadal's previous best start to a season came in 2014, when he won 11 matches before losing to Stan Wawrinka in the Australian Open final.
He will play Tommy Paul for a place in the Acapulco semi-finals.
Nadal, 35, could then meet world number two Daniil Medvedev, who he beat in a thrilling Melbourne final in January.
"It's always important to win as quick as possible but the most important thing is to win," Nadal said after his 76-minute victory.
"Tonight has been straight sets - that's great news, and I'll try to be ready for tomorrow against a tough opponent."
Russia's Medvedev needed just 64 minutes to beat Spain's Pablo Andujar 6-1 6-2 and keep his bid for the world number one ranking moving.
Medvedev, who faces Yoshihito Nishioka next, will replace Novak Djokovic at the top of the rankings if he wins the title in Mexico.
British number one Cameron Norrie was also among the winners, beating American John Isner 6-7 (2-7) 6-3 6-4.
World number four Stefanos Tsitsipas registered the quickest completed victory with a 47-minute 6-1 6-0 thrashing of American qualifier JJ Wolf.
Greek Tsitsipas will play American Marcos Giron next, while Norrie faces Germany's Peter Gojowczyk.
