The second Thursday at the Australian Open means it is time for some semi-final action in the singles, and a blockbuster match between Naomi Osaka and Serena Williams is set to kick-off proceedings as the fans return to Melbourne Park.
We take an in-depth look at the three semi-finals taking placing at the Rod Laver Arena on Thursday.
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The heavyweight clash

Naomi Osaka (Japan) [3] v Serena Williams (USA) [10]
Osaka leads H2H 2-1 – last meeting 2019 Toronto QF, Williams won 6-3 6-4
The final before the final? Karolina Muchova and Jennifer Brady would perhaps like to think otherwise, but there is no denying that the winner of Naomi Osaka v Serena Williams will be the heavy favourite come Saturday’s final in Melbourne.

‘Serena may be the GOAT but she still needs to step up’ – Wilander on Williams

This will be the fourth instalment of Osaka-Serena, and while the standout meeting so far is that US Open final in 2018, there is a real chance here for a spectacle in front of the returning supporters.
Back at Melbourne Park, the crowd could well witness a classic, but with their meetings so far all finishing in straight sets, that trend may have to change if it is to become a match to remember.
The pair also met in Adelaide last month in an exhibition which Williams won 2-6, 6-2, 7-10 – there’s not too much to read into that, but given both players have only dropped a set all tournament, it really does feel like a toss of a coin as Osaka seeks Grand Slam No. 3 and Williams, of course, a record-levelling No. 24.

'I always watch Serena's matches' - Osaka's reaction to beating Hsieh in straight sets

The semi-final few predicted

Karolina Muchova (Czech Republic) [25] v Jennifer Brady (USA) [22]
Muchova leads H2H 1-0, winning their only meeting 6-3 3-6 7-6 in Prague round-of-16 in 2019
Few will have predicted it would be the 22nd and 25th seed going head to head for a place in the final, but the pair have earned their right to be here after some terrific wins.

Highlights: Barty knocked out by Muchova in shock comeback

Muchova has claimed some huge scalps, beating world No 1 Ash Barty in the previous round as well as Elise Mertens and Karolina Pliskova, and the 24-year-old Czech will be confident of reaching his first ever Grand Slam final.
Meanwhile, Brady has predominantly avoided seeded opposition, having only faced 28th seed Donna Vekic so far, but nevertheless the American has impressed, most recently when fighting from a set down to beat compatriot Jessica Pugula.
This one feels too tight to call, but the wins Muchova has collected along the way here could give her the edge.

Highlights: Brady wins all-American clash to reach semi-finals

The World No 1 meets The Qualifier

Novak Djokovic (Serbia) [1] v Aslan Karatsev (Russia) [Q]
This will be the pair's first meeting
Qualifier Aslan Karatsev has already tamed three seeds this tournament in Diego Schwartzman, Felix Auger Aliassime and Grigor Dimitrov, but now – the biggest test of all, the toughest in the men’s tennis.

Highlights: Djokovic digs deep to beat Zverev and reach semis

Facing Novak Djokovic at his “happy place”, Karatsev will need to play the match of his life in what will be the pair’s first ever meeting.
His best hope could be to capitalise on a Djokovic dip should the Serbian cut a depleted figure, but the world No 1 has a ninth Australian Open in his sights, and that means he will take some stopping after already battling past Taylor Fritz, Milos Raonic and Alexander Zverev.
Djokovic in three feels like the most likely outcome, but qualifiers have defied the odds at Grand Slams before, and Karatsev will be out to do so again.

'He's got nothing to lose' - Henman on threat of Karatsev against Djokovic

ORDER OF PLAY - THURSDAY, FEBRUARY 18

ROD LAVER ARENA

Not before 3am UK time
  • Naomi Osaka (Japan) [3] v Serena Williams (USA) [10]
  • Karolina Muchova (Czech Republic) [25] v Jennifer Brady (USA) [22]
Night session - 8.30am UK time
  • Novak Djokovic (Serbia) [1] v Aslan Karatsev (Russia) [Q]
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