Rafael Nadal is taking nothing for granted in his Australian Open semi-final against Dominic Thiem despite owning a 100 percent record at Grand Slams against the slick Austrian.
At stake for both men is a last-four clash against either resurgent veteran Swiss Stan Wawrinka or German young gun Alexander Zverev.
Nadal was stretched to four sets for the first time in the tournament against explosive Australian Nick Kyrgios in the fourth round.
But the Spaniard warned he was getting better by the day as he looks to add to his 2009 Melbourne Park title and draw level with Roger Federer on 20 Grand Slam crowns.
"I think I am moving in the right direction. Every day I'm playing a little bit better," said Nadal, who is aiming for a seventh Australian Open semi, while Thiem is gunning for his first.
The two have met 13 times before and Nadal holds a 9-4 edge but 5-0 in Grand Slams, where he has claimed three of his last four victories over the Austrian.
Thiem was the man he beat in the last two French Open finals and the top seed has a lot of time for how the 26-year-old goes about his business.
"Very tough match. He's playing well. I saw him play (fourth round) against Gael (Monfils). He was playing a very high level of tennis," said Nadal.
"We know each other well. He's a player that I like a lot, the way that he works, the way that he plays, and the way that he tries his best always.
"It is a match that's going to be a tough one, but will be interesting. I know I have to be at my best to have chances."
Thiem took Nadal to four sets in last year's French Open final and pressed him to five in the 2018 US Open quarters, stunning the Spaniard by winning the opening set 6-0.
"I couldn't be happier to be in the quarter-finals," he said, as he continues his search for a maiden Grand Slam title. "I'm also very excited (to play Nadal)."
- 'One of the toughest players' -
Like Thiem, Zverev is seen as one of the players capable of breaking the stranglehold of Nadal, Roger Federer and Novak Djokovic at the Major tournaments.
But he must first get past Wawrinka, who is incredibly the only man other than the three greats to win the Melbourne Park title since 2006.
Wawrinka upset the traditional order in 2014 when be beat Nadal and went on to win two more Grand Slams -- the French Open in 2015 and US Open a year later -- before knee surgery in 2017 halted his march.
Now ranked 15, he said after upsetting fourth seed Daniil Medvedev to set up the Zverev clash that he was playing his best tennis since the surgery, with the passion to win another Slam still burning bright at 34.
"I've been feeling great on the court, on the practice court, putting a lot of work in physically and tennis-wise," said Wawrinka, who will have to overturn a 0-2 record against the seventh seed.
"Zverev, he's been in the top 10, top five since few years now. It's going to be a difficult match, for sure."
Zverev, who has huge potential but has yet to go beyond the quarter-finals in 18 Grand Slams, knows he has his work cut out against one of the toughest and most experienced competitors around.
"He showed why he's a Grand Slam champion, beating Medvedev, coming back from two-sets-to-one down, playing great tennis. He's still one of the toughest players to play, especially here in Australia," said the 22-year-old.