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Novak Djokovic advanced to the Australian Open quarter-finals in straight sets, while Kei Nishikori and defending champion Stan Wawrinka will meet in the last eight after respective victories on Monday.
Gilles Muller was hardly disgraced as Serbian world number one Djokovic showed his class when it mattered most in a 6-4 7-5 7-5 win.
Competing in his first fourth-round match at the Australian Open, Muller was not overawed by the occasion on Rod Laver Arena as the 31-year-old hit 47 winners.
However, Djokovic's superior quality shone through, with the four-time Australian Open champion limiting his unforced errors to 16 compared with Muller's 32 after a little more than two hours on court.
Djokovic – into his eighth successive quarter-final at the event – will now face eighth seed Milos Raonic for a place in the semis having not dropped a set.
Canadian Raonic survived a three-hour five-setter to beat Feliciano Lopez.
Raonic had two match points against the Spaniard in the fourth set tie-break but eventually sealed his spot in the quarter-finals via a 6-4 4-6 6-3 6-7 (7-9) 6-3 victory.
Fifth seed Nishikori was largely untroubled as he got past ninth seed David Ferrer in straight sets, winning 6-3 6-3 6-3.
The US Open finalist was the aggressor, tallying 43 winners to Ferrer's 14, and only dropping serve once.
Third seed Wawrinka had a much tougher time as he needed four sets to see off Guillermo Garcia-Lopez.
In 2014, Garcia-Lopez was Wawrinka's reminder that grand slam tennis was not all plain sailing when the Spaniard beat him in the first round at the French Open.
This year, Wawrinka reminded Garcia-Lopez of the status quo - the Swiss was the title-holder, the Spaniard was in new territory.
Never before had Garcia-Lopez reached the fourth round at Melbourne Park, like Wawrinka had never won a major 12 months back.
But Garcia-Lopez did not create his own history, Wawrinka instead added to his own remarkable narrative in Australia - the fourth seed progressing 7-6 (7-2) 6-4 4-6 7-6 (10-8) in three hours two minutes.
Garcia-Lopez blew a gilt-edged opportunity to take the clash to five sets when he held five set points in the fourth-set tie-break, but he could not convert.