World number one Rafael Nadal lost his first set of the tournament but rode out a spirited challenge from Nick Kyrgios to move into the quarter-finals of the Australian Open for the 12th time with a 6-3 3-6 7-6 (6) 7-6(4) victory.Former champion Stan Wawrinka emerged from a mid-match loss of confidence to battle past Russian fourth seed Daniil Medvedev to reach the quarter-finals with a 6-2 2-6 4-6 7-6(2) 6-2 victory. Earlier, seventh seed Alexander Zverev of Germany strolled past childhood friend Andrey Rublev 6-4 6-4 6-4 on Monday to end the Russian’s 15-match winning streak and book his maiden quarter-final spot.
