The scene was set for a day of explosive tennis as the majority of the top 10 from the men’s and women’s draws came out to play. The levels of expectation from the crowd were high as they entered Melbourne Park on day four, undoubtedly with a sense of what the vicious conditions would bring. Once again, it was an incredibly hot day with temperatures tipping 112 degrees. Players were seemingly not any more prepared for what for awaited them on the court. Despite this, there was still a great deal of quality tennis on show, starting with the first match on Rod Laver Arena.

The first match of the day proved to be the match of the tournament so far as world No. 3 Russian Maria Sharapova took on 72nd-ranked Italian Karin Knapp. Such a disparity in rankings as well as Sharapova’s victory in their only previous meeting suggested another routine win for the third seed. With the crowd unsure what to expect from both players in such oppressive conditions, the match would prove to be the exact opposite of a cakewalk for the Russian.

It was a shaky start to the match for Sharapova as she was broken in the third game by the wiry Italian, who managed to match Sharapova in the baseline department. However, with a high first=serve percentage of 71%, the Russian found her composure in the sun. She hit 14 winners to break Knapp in the fourth, the sixth and the eighth games to take the set 6-3. After keeping her cool in what were undoubtedly some of the toughest conditions Sharapova would have ever experienced, she was expected to race away with the match at that stage. But that was far from what unfolded on Rod Laver Arena.

The second set was a test of who could perform under the conditions. And the player that came to the fore was the Italian world No. 72, who limited her unforced errors and hit winner after winner to break Sharapova in the third and 10th games. Knapp, who served poorly in the first set, also improved her first-serve percentage significantly and converted both of her break point. Knapp won the second set 6-4 with play that reflected someone much above her ranking while perhaps taking advantage of Sharapova’s struggles in the cauldron. 

After a 10-minute break due to the heat at the end of the second set, Sharapova and Knapp reignited their dual like a pair of gladiators in front of thousands of enthralled fans. And they did not disappoint.

The third set must be described as grueling. Each player showed incredible fortitude to continue competing at such a high quality in what can only be described as ferocious conditions. Both players struggled to achieve a first-serve percentage higher than 50%, and this resulted in neither player being able to consistently hold her serve. Breaking each other at will, it became a stalemate, and it would be the player who could hold their nerve and their serve who would eventually win the match.

The atmosphere inside Rod Laver Arena seemed to be really heating up when Sharapova was called for time violation while being up a break and serving at 4-3. And the arena almost erupted when Knapp broke Sharapova to level the set at 5-5. Both players were clearly nervous, which showed as they challenged unwisely and committed strings of unforced errors.

At 6-6 in the third and final set, the heat policy was implemented by Australian Open officials. This meant that play was abandoned on the outside courts, and the roofs were to be closed on both Rod Laver and Hisense Arenas. The policy states that a roof is only to be closed at the conclusion of a set, though, so the match between Sharapova and Knapp remained under scorching blue skies. The toll of the conditions showed on both players as they retreated to the shade between points.

Despite the condition,s both players left nothing in the tank. Knapp and Sharapova constantly fought it out in long, exhausting baseline rallies that regularly passed 15 strokes. Coming within two points of victory in the 16th game, Knapp couldn’t break her opponent as Sharapova, like the proverbial wall, would not yield. Finally, at 30-40 in the 17th game, Knapp relented and shot a backhand long to hand Sharapova the break and make it 9-8.

The final game felt as if it lasted the duration of the entire match. Sharapova claimed the vital first point before tightening up and making three double faults, handing Knapp an opportunity to level it at 9-9. But the Russian this time would not surrender the break as Knapp’s 55th unforced error sealed the victory for the world No. 3 and condemned the underdog to a gut-wrenching loss.

In the post-match media conference, Sharapova was overjoyed with her win.

“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,” Sharapova exclaimed. “I got through it, and sometimes that's what's important.”

But, despite the win, she was a little unsure about whether they should have been forced to play in those hot conditions

“It's a tough call. I think the question I have is no one really knows what the [temperature] limit is,” said the refreshed-looking Russian. “Not the players, the trainers themselves. When you ask them when the roof will be closed, no one actually knows what that number is in comparison to humidity or the actual heat.”

The 26-year-old also said that officials probably should consider the weather in advance and make a decision when play can be stopped in the final set.

“In the third set for the women and the fifth set for the men, if you know that there is no tiebreaker, officials can't just rely on ‘maybe the set will go fast and the set will be over and will we will be off court,’ because we have no tiebreaker in that last set. So that's what you have to consider,” a relieved but concerned Sharapova said.

In Knapp’s post-match media conference, she spoke less boldly about the issue.

“I think maybe they could change some rules because it's not the same like playing under the roof or with the sun,” a visibly exhausted Knapp said. And when she was pressed on the officials’ handling of the heat policy, she was frank. “I think it helped me a bit the 10 minutes after the second set. We went to the locker room and we could cool down a little bit.  But I think they should change some rules.”

Knapp was ultimately philosophical today in defeat but said she would take a lot out of her epic match moving forward.

“It gave me confidence, because Maria is one of the three best players of the world. So getting to play games like this gives me confidence,” the Italian said. “I played a great match and it was so close. It's normal at the end [to feel] a little bit disappointed. You want to win at the end because it was so close, but I played a great match and am looking forward to doing many matches like this.”