The last of the record-breaking heat is expected to leave Melbourne today as a cool change sweeps across the city, but some things always stay the same:

you should never get Andy Murray angry.

On a day when play was suspended as temperatures topped 43°C and rain and lightning interrupted play, Murray survived humid conditions under the roof and a hell-for-leather opponent in Vincent Millot to reach the third round.

Murray was cruising at 6-2, 6-2 only for Frenchman Millot to go for broke and storm into a commanding lead. However, after saving a set point at 1-5, the Wimbledon champion reeled off an incredible 23 straight points to advance to the last 32 in straight sets.

The Scot looked to have lost focus as Millot teed off in the third set to great success but, unwittingly, his mistake was to raise his hands to the crowd to whip up support.

"I know what it's like," said Murray, still sweating more than 20 minutes after his match was completed. "When I played on a court like this for the first time you get so fired up that the best thing to do is just concentrate on what you're trying to do.

"Whereas it might have distracted him a little bit, it re-focused me more and my intensity went up around that period and I turned it around."

Murray was grateful to be scheduled as the last match on, even more so after seeing his brother, Jamie, struggle with heatstroke hours after his doubles victory with John Peers.

The Scot admitted it may have affected his focus and a few grabs at his back prompted some anxious looks, four months after surgery to cure a long-standing issue. But after he put away a driven backhand volley to save the set point at 1-5, he was himself again and whizzed through 23 straight points - his greatest points streak - to seal a meeting with Feliciano Lopez of Spain.

Murray arrived in Melbourne tempering his expectations because of a lack of match practice but freshness also may count and he seems comfortable as he heads to the third round. "The first match I played very well," he said. "The more you get tested, you raise your game and today I didn't hit the ball that well. I'm going to be a bit inconsistent but if I can get myself into the second week, stranger things have happened."

Murray has beaten Lopez seven times out of seven but had a tough match with him at the US Open two years ago and the Spaniard promised to give the Scot something different to look at. Murray, though, has a superb record against left-handers, knows Lopez's game inside out and is ready for the challenge.

"Feliciano doesn't give you loads of rhythm but I guess just knowing his game, understanding the way he's going to play and the level he's going to bring to the court will make it a little easier for me to be more consistent," he said. "It's natural that as I play more matches, I'll feel better and be more comfortable but, being 5-1 down in the third set in such humidity; these are all little tests for me that I've managed to get through so far. Feli will be another one."

If Murray was lucky to avoid the worst of the heat, then so were Rafael Nadal and Roger Federer, whose matches began indoors on Rod Laver Arena and Hisense Arena respectively after the suspension of play.

Nadal gave 17-year-old Australian Thanasi Kokkinakis a bit of a lesson as he beat the world No.570 6-2, 6-2, 6-4, looking in good form as he set up a mouthwatering match with Frenchman Gael Monfils.

So too Federer, who shook off the ignominy of being scheduled away from Rod Laver Arena for the first time in a decade to blast past the Slovene Blaz Kavcic 6-2, 6-1, 7-6 and now meets Teymuraz Gabashvili of Russia. "It's not really different to Rod Laver Arena really," the 17-time grand slam champion said of the Hisense Arena, the second-biggest court here at Melbourne Park. "I don't feel like you need to make an adjustment. The crowds were really nice. Great atmosphere over there. I was happy playing there."

The biggest shock of the day came well past midnight when Argentina's Juan Martin Del Potro, who won the warm-up event in Sydney, was ousted in five sets by unheralded Spaniard Roberto Bautista Agut.

If the big names in the men's event escaped the heat, the same could not be said for the women with Maria Sharapova forced to play well over three sweltering hours before defeating Italy's Karin Knapp 6-3, 4-6, 10-8 in a close match.

Two-time defending champion Victoria Azarenka and former world No.1s Caroline Wozniacki and Jelena Jankovic also all progressed to round three.