The biggest shock of this Australian Open so far arrived in front of a dwindling crowd on Court 2, when Roberto Bautista-Agut eliminated the No 5 seed and former US Open champion Juan Martin del Potro in the second round.
Despite running to five sets and three hours and 53 minutes, the match was mostly played at a manageable 27C and afterwards the ever-gentlemanly Del Potro refused to make any excuses, complimenting his opponent.
"In every moment, he played an unbelievable shot," said Del Potro of the Spaniard. "In break point down, he served well. He made winners with forehands, backhands and he played always to the line."
There was more drama in Margaret Court Arena, where Nick Kyrgios, the hugely talented Australian 18-year-old, stood on the verge of a career-best victory against the No 27 seed Benoit Paire. However, Paire edged his way back into the contest and then Kyrgios was struck down by drastic leg cramps and the Frenchman came through 6-2 in the deciding set.
Meanwhile, the Australian Open's chief medical officer, Dr Tim Wood, tried to explain why he expected players to keep performing in temperatures of around 42C.
"We evolved on the high plains of Africa chasing antelope for eight hours under these conditions," he said.
"There will be some players who complain and no one is saying it is terribly comfortable to play out there, but, from a medical perspective, we know man is well adapted to exercising in the heat.
"Whether it is humane or not is a whole other issue." (© Daily Telegraph, London)