Rafael Nadal's staggering admission about his injury battle after winning his Australian Open semi-final

Spanish superstar Rafael Nadal admits he was "surprised" that after a recent battle with heatstroke, he could make it to the court let alone defeat Italian No.7 seed Matteo Berrettini.

Nadal is now one match away from overtaking rivals Roger Federer and Novak Djokovic at the top of the leaderboard by winning Grand Slam No.21. Despite having to race the clock to recover from a sapping five-set quarter-final in time for his match-up with Berrettini he took Rod Laver Arena in good shape and won 6-3 6-2 3-6 6-3.

While another spot in a Grand Slam final is an impressive milestone for the 35-year-old, so too was his ability just to make it to the Australian Open this year following a four-month layoff due to a foot injury, as well as battle with COVID-19 in December.

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The Spaniard entered today's semi-final three days after suffering heatstroke during his quarter-final win over Canadian Denis Shapovalov, a match that lasted four hours and eight minutes in scorching temperatures.

"Being honest, the day after [the win against Denis Shapovalov], in the morning I felt much better which really surprised me because I didn't practice for it," Nadal told Nine's Jim Courier during his on-court interview.

"Sometimes two days in the middle [between matches] are difficult to manage, but in this case, I was lucky to have those two days... yesterday was a day to push it a bit, keep working hard because I knew today would be a big challenge."

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Nadal added that he would have preferred today's semi-final to be played with the roof open, after Courier inquired about how he felt playing in cooler temperatures and with rain creating heavier conditions.

"As everyone knows, I'm more of an outdoor than indoor player, but I think the stadium looked amazing closed with an amazing crowd... I can't complain at all," Nadal replied.

"I knew before the match that the roof would be closed, but you know what, one month and a half ago, I didn't know if I would be able to play tennis.

"So it doesn't matter if it's outdoor or indoor today, I just wanted to enjoy to try my best."

Since winning the Australian Open in 2009, Nadal has reached the final on four occasions but has fallen short each time.

Nadal has the chance to become just the fourth player to win at least two titles at each Grand Slam, something even Federer has not been able to achieve.

"For me, it's all about the Australian Open more than anything else," he said.

"It is just an amazing event, that as I said a couple of days ago now, I have been a little bit lucky in my career with some injuries.

"At times I play good finals against Novak in 2012 and Roger in 2018.

"I was lucky to win once in 2009, but I never thought about another chance in 2022.

"I will just enjoy the victory today and after that, I will try my best."