Maria Sharapova thinks there should be greater clarity about the Australian Open's extreme heat policy after battling for more three hours in roasting conditions to reach the third round.
The third seed was on court for three hours and 28 minutes on her way to a 6-3 4-6 10-8 victory over Italy's Karin Knapp.
Tournament referee Wayne McKewen makes the call when to suspend play but there is no fixed temperature that brings the rule into effect, with humidity, wind direction and the immediate forecast all taken into account.
Conditions were deemed unplayable on Thursday as the thermometer hit 42C yet on Tuesday it was above 40C for five hours and play continued.
Sharapova said: "There is no way getting around the fact that the conditions were extremely difficult and have been for the last few days.
"It's a tough call. I think the question I have is no one really knows what the limit is. Not the players or the trainers.
"We have never received any e-mails or warnings about the weather or what to do. Actually, I did receive one while I was in the ice bath a few minutes ago, and I was like, 'That's a little too late'."
A quirk of the policy means, even when it is fully implemented, players are required to finish the set before matches are suspended on the uncovered courts and the roofs are shut on Rod Laver and Hisense Arenas.
That meant Sharapova and Knapp had to finish their match even though, in theory at least, it could have gone on indefinitely.
The Russian said: "Officials can't just rely on maybe the set will go fast and the set will be over and we will be off court. I think our match was an example of that."
Sharapova also argued that the time limit of 20 seconds between points should be extended or suspended when conditions are extreme.
The third seed was given a time violation during the deciding set, and she said: "Anywhere else, it's fine. If that's the speed of the game that's absolutely fine. But in these conditions, I mean, let it go."
Sharapova accepted she largely had herself to blame for the length of time she spent on court.
It was an error-strewn performance from the 26-year-old, who served 12 double faults.
A loose game allowed Knapp to take the second set and the Italian, whose career was interrupted by a heart condition that required two operations, then saved three match points when Sharapova served for it at 5-4.
At 7-8, Sharapova was two points from defeat but she hung on, broke the Knapp serve and finally clinched victory on her fourth opportunity.
The Russian, who missed the last part of the 2013 season with shoulder problems, said: "I'm really happy to get through. 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. I got through it and sometimes that's what's important."
Sharapova next meets France's Alize Cornet, who was in tears at the end of her 6-3 4-6 6-4 win over Camila Giorgi.
She said: "I think I was very brave, like every player at this tournament in these conditions. I really tried to hold my frustration and hold everything I was thinking about during the match and finally at the end I just let it go. I was emotional."
Varvara Lepchenko was the player to struggle most on Thursday, the American taking a medical time-out during the second set of her second-round match against Simona Halep.
Lepchenko lay down across two chairs while a doctor examined her and had ice rubbed over her body before continuing. Having won the first set she managed only one more game in a 4-6 6-0 6-1 defeat.
Lepchenko said: "I think they definitely should have just not started the matches in the first place. In the second set I couldn't focus on my returns, I couldn't see the ball."
Caroline Wozniacki and Agnieszka Radwanska both had the luxury of playing their matches with the roof closed.
Tenth seed Wozniacki won a topsy-turvy clash with American Christina McHale 6-0 1-6 6-2 while fifth seed Radwanska was a 6-0 7-5 winner over Olga Govortsova.