With the extreme heat policy activated and the Rod Laver Arena roof closed, it was pressure as opposed to heat that both Christina McHale and 10th seed Caroline Wozniacki felt at various stages of this see-sawing second-round match.
Surprisingly it's world No.62 McHale who led their head-to-head 2-1 prior to today's match. But Wozniacki squared the ledger with Thursday's 6-0 1-6 6-2 win in one hour and 43 minutes at Rod Laver Arena.
The 10th-seeded Dane is regularly referred to as the sport's 'Golden Retriever' for her ability to chase down every ball and wait for the error to come from the other side of the net. But in the first set Wozniacki was more like a spider, building a web and waiting for her prey to fall into it.
And McHale, who plays a similar game to the 10th seed, duly fell for the trap her opponent had set.
A total of 13 unforced errors to Wozniacki's three was the story of the first set, which lasted just 28 minutes.
McHale went for too much too early, pushing shots wide or long in an attempt to hit winners. This suited Wozniacki to a tee – the Great Dane simply kept the ball in play and watched as McHale dug herself an increasingly larger hole with every error.
Thankfully for the American the second set started in a more positive fashion - breaking Wozniacki in the opening game was a step in the right direction.
With nothing to lose, McHale started to swing a little more freely and her shots started to find their mark. Now it was Wozniacki who was feeling the pressure and she duly started to make errors as McHale grew more bold, taking the set 6-1 to level the scores.
But Wozniacki wasn't the world's No.1 player for 67 weeks for nothing and this match had one more twist to come.
With two break points to take a 2-0 lead early in the deciding set, McHale made two crucial errors that allowed Wozniacki to hold serve.
It was all the Dane needed. She made McHale pay, breaking her in the third and fifth games to build what would prove to be an unassailable lead.
"I started off really well, I was very aggressive in the first set … she stepped it up a litte bit [in the second set]," said Wozniacki.
"In the third set i just tried to fight for every point … I think my fighting spirit today pulled me through."
And Wozniacki will need to keep that fighting spirit going when she takes on Spain's Garbine Muguruza in the third round.