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NOW: Alexander Zverev beats Carlos Alcaraz 6-1 6-3 6-7 (2-7) 6-4 in men's quarter-finals
German will play Daniil Medvedev, who beat Hubert Hurkacz 7-6 (7-6) 2-6 6-3 5-7 6-4
Qualifier Dayana Yastremska beats Linda Noskova in straight sets to reach first major semi-final
Zheng Qinwen beats Anna Kalinskaya 6-7 (4-7) 6-3 6-1 to reach women's singles semi-finals
Britain's Neal Skupski and American partner Desirae Krawczyk reach mixed doubles final
Medvedev 7-6 (7-4) 2-6 6-3 5-7 6-4 Hurkacz
Image source, Getty ImagesDaniil Medvedev seals it with a forehand!
After five sets, and four hours, the third seed is through to his third semi-final at the Australian Open.
*Medvedev 7-6 (7-4) 2-6 6-3 5-7 5-4 Hurkacz
Hurkacz does brilliantly to keep getting the ball back in play under intense pressure, long enough to see Medvedev drop a shot into the net.
One more match point to come.
*Medvedev 7-6 (7-4) 2-6 6-3 5-7 5-4 Hurkacz
Medvedev produces an ace to turn the game in his favour before setting up to two match points with a forehand.
*Medvedev 7-6 (7-4) 2-6 6-3 5-7 5-4 Hurkacz
Hubert Hurkacz finds the back of the court with a forehand to beat Daniil Medvedev, who had made his way to the net ready to move a step closer to victory. 0-15.
*Medvedev 7-6 (7-4) 2-6 6-3 5-7 5-4 Hurkacz
Hurkacz makes no mistakes as he holds serve to love to force Medvedev to try and serve this out.
Do we have more twists and turns to come, or is the third seed destined for his eighth major semi-final?
Medvedev 7-6 (7-4) 2-6 6-3 5-7 5-3 Hurkacz*
Medvedev has to try something a bit different and goes for the serve and volley to save the break point.
Incredible! The crowd erupts as Hurkacz edges a stunning point with a volley at the net after somehow reaching a drop shot and lifting his return over the advanced Medvedev to stay alive in the game.
The Poland flags are being waved as Hurkacz's fans sense another fightback, but this time Medvedev is able to keep his composure to get to safety.
*Medvedev 7-6 (7-4) 2-6 6-3 5-7 4-3 Hurkacz
Wow! Is it going to happen again to Daniil Medvedev?
Hubert Hurkacz reaches break point.
*Medvedev 7-6 (7-4) 2-6 6-3 5-7 4-3 Hurkacz
Hubert Hurkacz isn't quite done yet. An accurate forehand brings him to 30-30 on Daniil Medvedev's serve.
He'll know there's every chance of getting back into this after what happened to Medvedev at the end of the fourth set.
*Medvedev 7-6 (7-4) 2-6 6-3 5-7 4-3 Hurkacz
Is that the match right there?
Hurkacz falters, conceding the break to 15, to leave Medvedev once again within two games of victory.
That didn't go too well for the Russian when leading 4-2 in the fourth set, though.
Medvedev 7-6 (7-4) 2-6 6-3 5-7 3-3 Hurkacz*
The commentator's curse.
Hubert Hurkacz has a rare dip on serve and a missed backhand gives Daniil Medvedev two break points.
A couple of huge points coming up...
Medvedev 7-6 (7-4) 2-6 6-3 5-7 3-3 Hurkacz*
A tie-break is shaping up to be the most likely outcome right now.
Another solid game from Daniil Medvedev confirms a hold to 15 and that's three games in a row now that neither player has taken more than a single point off the server.
Jonathan Jurejko
BBC Sport in Melbourne
Whenever a match enters a fifth set, we immediately look for each player's stats in deciders.
They can often provide clues about their mental and physical durability, but certainly won't give us a definitive answer.
Just as well for Medvedev.
He has lost 10 of his 15 career five-setters. But he has won the last two, including his second-round win over Emil Ruusuvuori.
Hurkacz has a winning majority of nine victories from his 16 - also including one in the Melbourne second round this year against qualifier Jakub Mensik.
*Medvedev 7-6 (7-4) 2-6 6-3 5-7 2-3 Hurkacz
Hurkacz maintains scoreboard pressure on Medvedev with another straightforward hold of serve.
Five games into the deciding set and we're still none the wiser to knowing who will be in the final four at Melbourne Park.
Or are we? Over to statman JJ...
Medvedev 7-6 (7-4) 2-6 6-3 5-7 2-2 Hurkacz*
A comfortable hold for Daniil Medvedev as the clock moves past three and a half hours of play on Rod Laver Arena, but only after Hubert Hurkacz picks off a serve with a bullet forehand.
Jonathan Jurejko
BBC Sport in Melbourne
Not only is Hurkacz receiving a jot of confidence from the crowd, he is perhaps buoyed by the fact he knows he has the game to trouble even Medvedev.
The proof has been in their previous meetings.
Hurkacz leads 3-2 in their head-to-head and has the knowledge he has done it over five sets.
The Pole claimed victory in their only previous Grand Slam contest, winning a five-set contest in the fourth round at Wimbledon in 2021.
*Medvedev 7-6 (7-4) 2-6 6-3 5-7 1-2 Hurkacz
A tired looking backhand from Hubert Hurkacz this time, which drops into the net for 30-30.
Can Daniil Medvedev apply a bit of pressure for the first time in what feels like quite a while?
Nope. Hurkacz goes for the serve and volley approach to settle his latest game.
Medvedev hasn't had a look at a break point since the opening game of the fourth set.
Medvedev 7-6 (7-4) 2-6 6-3 5-7 1-1 Hurkacz*
Daniil Medvedev needs to dig deep here. A backhand finds the net to bring Hubert Hurkacz to 30-30 and there's an increasingly weary look about the Russian, but he does what he needs to in his first service game of the decider.
*Medvedev 7-6 (7-4) 2-6 6-3 5-7 0-1 Hurkacz
A positive start to the final set by Hubert Hurkacz, who holds serve comfortably to make it six games in seven.
Medvedev 7-6 (7-4) 2-6 6-3 5-7 0-0 Hurkacz*
There's no mistaking who has the momentum right now.
Hubert Hurkacz has won five of the last six games in this match to enter the fifth set believing a place in his first Australian Open semi-final is there for the taking.
Image source, Getty Images
Image source, Getty ImagesJonathan Jurejko
BBC Sport in Melbourne
Well, well, well.
Who saw that coming?
Medvedev looked to be on course to victory, but sloppy errors started creeping in and Hurkacz took full advantage.
The swathes of Polish fans jump for joy before both players go off for court for a breather.