Nadal, Federer waltz through

Tennis Australian Open

Rusty Sharapova, Murray enter pre-quarterfinals; Muguruza stuns Wozniacki

Rafael Nadal beamed with delight after laying down an emphatic marker with a brilliant display of all-court tennis to charge into the last 16 of the Australian Open on Saturday.

The Melbourne heatwave may have broken but arch-competitor Nadal was still bathed in sweat after his two-hour 6-1, 6-2, 6-3 demolition of the talented but error-prone Gael Monfils.

Roger Federer earlier boasted of his fitness, Maria Sharapova felt a bit rusty and Andy Murray berated himself but all three eased into the second week. Victoria Azarenka remained on course for her third straight title but may find the next hurdle trickier after setting up a fourth round tie against Sloane Stephens, who she beat amid controversy in last year's semifinals.

While there was relief all round at the cooler temperatures after four days of stifling heat, Milos Raonic and Caroline Wozniacki both felt the stinging burn of an upset.

Nadal never looked in any danger of an early departure, barring a brief injury scare when he jarred his foot early in the second set.

Such was his dominance after he suppressed the Frenchman's early charge, the Spaniard was at a loss to pick out an element of his game that pleased him most.

"I think I have to say that I played well from everywhere, no?," he said. "Tonight I think I played a great match ... (but) just one very good day. That makes me feel confident, but I am in the fourth round. That's all."

The top seed will play Kei Nishikori for a place in the quarterfinals after the Japanese ended American interest in the men's draw with a 7-5, 6-1, 6-0 win over Donald Young.

Federer looked at his own imperious best as he dismantled Teymuraz Gabashvili 6-2, 6-2, 6-3 to reach the fourth round at a Grand Slam without giving up a set for the 27th time.

The Swiss is aware that tougher tests lie ahead, starting with Frenchman Jo-Wilfried Tsonga in the next round, but was delighted to have rid himself of his back problem.

"I'm just happy not waking up like an old man," said the 32-year-old, who failed to get to a Grand Slam final for the first time since 2002 last year.

"It was a tough year last year and now for the last few weeks, I'm feeling much better... I've done the hard work and that's perhaps why I'm playing well. "

Murray's back problems are more recent and he admitted to feeling a bit of stiffness as he finds his feet again following surgery and four months on the sidelines.

Spaniard Feliciano Lopez gave him a big test in the first set tiebreak but faded after conceding the second and the fourth seed claimed his 14th straight victory over a left-handed opponent 7-6 (7-2), 6-4, 6-2.

"It's been a good start," said the Wimbledon champion. "Today was a big step up for me. Feliciano is a top 30 player. He's a tricky opponent to play. So it was a good test for me and I did well."

Murray next meets Stephane Robert, who prevailed 6-0, 7-6 (7-2), 6-4 over fellow lucky loser Martin Klizan – the first time a late replacement has reached the last 16 in Melbourne.

Sharapova continued to don her distinctive ice jacket at end changes despite the cooler weather as she beat France's Alize Cornet 6-1, 7-6 (7-6). Her boyfriend Grigor Dimitrov took a small step out of her shadow when he reached the fourth round of a Grand Slam for the first time by edging 11th seed Raonic 6-3, 3-6, 6-4, 7-6 (12-10).