The conditions were brutal, Maria Sharapova was way below her best and little-known opponent Karin Knapp was playing out of her skin.
All of which made the Russian third seed even prouder to have found a way to win 6-3 4-6 10-8 after three hours and 28 minutes of sweat and toil, allowing her to advance to the third round of the Australian Open on Thursday.
Sharapova blew three match points in the ninth game of a third set that lasted the best part of two hours.
Her serve was so shaky at times that she even had three double faults in the final game which she won when a backhand from Knapp - an Italian who has never beaten a top-10 player in a career played almost exclusively out of the spotlight - flew agonisingly long.
"We fought as hard as we could," said Sharapova.
"Quite honestly, she played some of the best tennis I've ever seen her play.
"I think you just get numb to (the heat), it just doesn't faze you any more."
The extreme heat policy was invoked early in the final set but it had no effect on the match, with the set completed with the roof remaining open on Rod Laver Arena.
Sharapova felt it should have been closed before the final set began.
She was also unhappy to have been hit with a time violation in a match where both players were searching for the shade at every available opportunity.
But still she won in a match which bore a striking resemblance to one played by Sharapova back in the first round of the 2007 Australian Open, when she was pushed to 9-7 in the deciding set by Frenchwoman Camille Pin in conditions the Russian later described as "inhumane".
"I'm really happy to get through," said Sharapova on Thursday.
"I worked really hard in the last few months and I wanted this match.
"I didn't play my best tennis; I didn't do many things well.
"But I got through it and sometimes that's what is important.
" ... when you win the match point you get off the court and no matter how you feel and how tough it was, I love those moments.
"That's why I play the sport."
The unseeded Knapp had major heart surgery two years ago.
She was proud to have pushed Sharapova to the brink and also disappointed at not being able to finish the job.
"I know that it was hot for me, but I know it was hot also for Maria," she said.
"We were both fighting with the heat.
"It was really tough, but we didn't stop."
Sharapova, 26, has won each of the four majors once, with her sole Australian Open title coming back in 2008.
Her next opponent at Melbourne Park will be French No.25 seed Alize Cornet, who was also pushed to three tight sets on Thursday before seeing off the challenge of Italian Camila Giorgi 6-3 4-6 6-4.
Former world No.1 Caroline Wozniacki from Denmark went the distance before finding a way past American Christina McHale 6-0 1-6 6-2.
No.5 seed Agnieszka Radwanska from Poland had an easier time of it, downing Belarussian Olga Govortsova 6-0 7-5.
Australian wildcard Olivia Rogowska lost 6-4 7-5 to unseeded Ukrainian Elina Svitolina.