MELBOURNE, Australia (AP) — The heat wave didn’t claim any major casualties at the Australian Open. Novak Djokovic and Serena Williams extended their winning streaks to move into the fourth round, and all except one of the leading contenders made it through to the weekend.

Five-time champion Williams saw off the worst of the searing, once-in-a-century conditions that scorched Melbourne for four straight days, beating Daniela Hantuchova 6-3, 6-3 yesterday.

Melbourne Park didn’t quite reach the forecast peak of 44 Celsius (111 Fahrenheit) — it did get to 43 C (109 F) — that had some players complaining about “inhumane” conditions.

Williams has never been one to be seriously affected by the heat, but even she had to admit she was looking forward to the cooler conditions expected from today. She also admitted to a little bit of relief after an injury to her sister, Venus, meant they had to withdraw from the doubles.

Djokovic used to struggle in the heat, but has grown accustomed to it with three consecutive Australian titles. He’s aiming to be the first man in the Open era to win four in a row, and thinks he’s getting there.

He benefited from the cool change that swept in late yesterday before his 6-3, 6-3, 7-5 win over Denis Istomin. He wrapped it up at 12:10 am, and thanked the crowd — including new coach Boris Becker — for staying past midnight.

The only time he was broken was serving for the match — he was clearly irritated but quickly recovered and finished it off two games later.

He has won 24 consecutive matches at Melbourne Park. It’s not in the league of Roger Federer’s reign at Wimbledon, but he is in contention to be the first man in the Open era to win four consecutive Australian titles.

Djokovic’s overall winning streak stands at 27 matches — he hasn’t lost since the US Open final last September, when he was beaten by a resurgent Rafael Nadal. He subsequently lost his number one ranking to Nadal, despite winning four straight tournaments at the end of 2013.

The other active major winners are either on the opposite side — Nadal, Andy Murray and Roger Federer play their third-round matches today — or out of the competition. Number five Juan Martin del Potro, the 2009 US Open champion, was the biggest casualty of the second round.

Of the contenders on Djokovic’s side, third-seeded David Ferrer beat number 29 Jeremy Chardy 6-2, 7-6 (5), 6-2 and number seven Tomas Berdych defeated Bosnian qualifier Damir Dzumhur 6-4, 6-2, 6-2.

Williams will set another record when she plays former number one-ranked Ana Ivanovic tomorrow — her 70th main draw match at Melbourne Park will be the most by any woman in the Open era.

Ivanovic had a 6-7 (8), 6-4, 6-2 win over 2011 US Open champion and local favorite Sam Stosur, while two-time finalist Li Na beat number 26-seeded Lucie Safarova 1-6, 7-6 (2), 6-3.

Williams’ win over Hantuchova was her 61st at the Australian Open, surpassing Margaret Court’s mark of 60.

Her focus, though, is clearly the four more wins it will take to deliver an 18th major title. She barely gave her latest record a thought in her post-match news conference yesterday.