With a barrage of 24 winners - including 10 aces - the No.1-seeded Williams dropped a 61 62 second round decision on Serbia's Vesna Dolonc, improving to 52-1 in second round matches at Grand Slams.
"I was happy just to get that win under my belt and have a chance to go to the next round," Williams said. "I think it was tough conditions out there. I think it keeps getting hotter and hotter. Every day is really hot. So it wasn't the plan, but it just so happened like that, and I'm happy to get through."
Williams was asked whether she's ever played in these kinds of hot and muggy conditions before.
"Yeah, for sure," she said. "I remember playing a couple for sure against Svetlana once, and then I remember one time playing against Mauresmo. I don't know what year it was. It was just super hot.
"So there have been a few. I played Victoria once in really hot weather too."
With five Australian Open titles to her name, clearly Williams is able to battle through it.
"I think I probably feel it more in my head, not necessarily in my chest. So far I've been okay. I've been training for a long, long time in the heat in Florida, as well as coming to Melbourne for years and years. So you just have to be ready for those hot conditions and just try to get through it on the day.
"It was definitely really hot today, but I just tried to take it in stride and do the best I could."
And what problems did her opponent, Dolonc, present her with? "I think she plays very solid," she said. "I don't think I had ever played her before. It's tough to go in front of an opponent you don't really know - you don't know what to expect, you don't know what to do. My coach kind of knew her game a bit.
"She was actually a really good player," the World No.1 added. "She hit a lot of deep shots and she was extremely fast. I definitely saw why she proceeded into the second round of the Australian Open."
More significantly, Williams tied Court's record for most match wins here. Court is also one of the women Williams is chasing for most Grand Slam titles - Court leads with 24, then Steffi Graf with 22, Helen Wills Moody with 19 and Chris Evert and Martina Navratilova with 18. Williams has 17.
Williams is trying not to feel the pressure - not just for that list, but all the others.
"To me there is always pressure. It always seems like I'm one of the favorites to win. But for me, I look at it as kind of exciting that I have an opportunity to go all the way. But with that being said, I have so many matches I have to win in order to do well and in order to lift the trophy. It's such a long way.
"I'll just have to play one match at a time."
Williams leads Hantuchova in their head-to-head series, 8-1, though Hantuchova's only win in the series did come in the pair's only match in Australia - right here in the same round eight years ago.