Wawrinka takes a deep intake of breath (at least he's trying to find his zen) after coughing up a double point on the first point. The Swiss still dancing, still jumping up and down in between points, hoping such movement will sprinkle some twinkle into his toes. Wawrinka back in contention, though, reining Djokovic back to 30-30 and an ace eases him to within a point of holding.

But Djokovic capitalises on sloppy Wawrinka errors and gathers his first set point. Wawrinka earns a temporary reprieve until the Serb produces a sizzling forehand winner down the line for a second set point. The ball then clips the net cord and Djokovic pounces with an irretrievable volley. Set over.

Djokovic moving his rattled opponent one way with a serve out wide and then the other with a crisp backhand into the corner. Wawrinka sprinting, not giving up, but his backhand dribbles into the net. Another mistake on the backhand from Wawrinka and Djokovic is 40-15 up. Fortune favours Wawrinka, momentarily at least, as a net cord goes his way. The Swiss raises his arm but looks a disgruntled figure, muttering something under his breath. The eighth seed has had better starts, he spoons a forehand wide and Djokovic is a game away from the set.

Jeremy Bates
Former British number one on BBC Radio 5 live sports extra

"The great champion that Djokovic is doesn't need a second invitation and on his first break point dominated the rally to establish a significant breakthrough."

Listen to live commentary on BBC Radio 5 live sports extra

Image source, AP

Djokovic's trainers are screeching as the second seed lunges from tramline to tramline, fetching and retrieving. The Serb reaches a deep Wawrinka volley but is long with his lob. Errors creeping into Wawrinka's game, though, a single-handed backhand wide by some distance and the Swiss then nets a forehand to present Djokovic with two break points. Wawrinka, edgy, nervy, and he folds - forehand into the tape and the Djokovic supporters are singing "Ole! Ole!"

Wawrinka is in his national colours - white top and blood red shorts with a dash of both colours on his trainers. The Swiss gambolling just behind the baseline as he prepares to face Djokovic's big serve. He nicks one point, but a mammoth second serve down the middle takes the Serb to 40-15. Wawrinka, though, approaches the net for the first time in this match and reaches out to put away a fine backhand volley. Questions being asked of Djokovic for the first time but no debate develops, the pair want to save such shenanigans for later on it seems. Wawrinka forehand long and that winds up the game.

There are a number of empty seats behind Djokovic as he faces the Wawrinka serve and it's a muted atmosphere in the arena at the moment as the crowd await for this match to explode into action. And after typing that the pair embark on an exquisite rally... 24 shots... and Djokovic can retrieve no more. His resistance falters and Wawrinka leaps 30-0 ahead. The Swiss extends his advantage and holds to 15 when Djokovic, at full stretch on the baseline, nets.

Jeremy Bates
Former British number one on BBC Radio 5 live sports extra

Image source, Reuters

"Andy Murray has done well so far to get through these straightforward matches after such a long lay-off. When you face someone of the stature of Federer you ramp up your competitive spirit to rise to the challenge. Murray has a great record against Federer and it's a question of how his body responds and we've seen indications that he's not far off his best."

First sight of Wawrinka's picture-perfect single-handed backhand but the shot proves not to be as effective as it is aesthetically pleasing. It goes long by a fraction to award Djokovic with another straightforward point. Both players readjusting their radars, making slight tweaks here and there after a couple of early errors. Djokovic screws a backhand wide for 30-30, but winds up the game thanks to an ace and an iffy Wawrinka return.

An ace from Wawrinka ensures he makes an equally confident start. The Swiss misses a makeable backhand volley, but Djokovic not yet returning with his usual gusto so it's a hold to 15 for Wawrinka.

Djokovic opens with two easy points and in just 60 seconds he has held to love. Wawrinka netting a backhand return before the Serb skips towards the net and deftly volleys to wrap up the game.

Djokovic and Wawrinka have finished their warm-up. The Swiss is swishing some juice around his mouth like a boxer before heading off to face the Djokovic serve. Seconds away.

Image source, Getty Images

Everyone likes a few statistics at this time of the day. There are, I think, statistics to prove it, or I could just be making that last bit up. Anyway, Novak Djokovic will reach his 15th consecutive Grand Slam semi-final if he gets the better of Stanislas Wawrinka today.

And there's more. This is his 19th consecutive Grand Slam quarter-final which means the Serb has reached the last eight at every Grand Slam since the 2009 French Open. Only Roger Federer (36) and Jimmy Connors (27) have notched more consecutive Grand Slam quarter-final appearances.

Midnight GMT:

Simona Halep (Rom) [11] v Dominika Cibulkova (Svk) [20]

Agnieszka Radwanska (Pol) [5] v Victoria Azarenka (Blr) [2)

Not before 03:00 GMT

Rafael Nadal (Spa) [1] v Grigor Dimitrov (Bul) [22]

08:30 GMT

Andy Murray (GB) [4] v Roger Federer (Swi) [6]

Piers Newbery
BBC Sport at Melbourne Park

"After a dramatic build-up with some thumping music reminiscent of the ATP Finals at the O2 Arena, the Rod Laver Arena roof pulls apart to reveal a bright, cloudy sky. Jim Courier and Lleyton Hewitt are courtside on media duty as Wawrinka and Djokovic walk on to what I'm guessing is AC/DC, as they like to keep things in-house. It's a paltry 19C, so if this goes to five sets like last year, it could be quite fresh by the latter stages."

The fans who had tickets for the day's play on Rod Laver Arena have disappeared and the litter they (probably) left behind has been cleared up. A fresh bunch of spectators are filtering into the grand venue and soon they will be cheering Novak Djokovic and Stanislas Wawrinka.

BBC Radio 5 live sports extra

Former world number one Mats Wilander has told BBC Radio 5 live sports extra he believes Murray can win this year's Australian Open.

"I think we're all expecting him to fight hard, have a good attitude and try to play the right way. His back injury gives this freedom to say 'I'm not back yet'. That can last through to the French Open. He can still win because he's a great player. You have to be ready for it, you have to be ready to be disappointed but you have to be ready to suffer. It's not going to be easy."

Simon Briggs
Daily Telegraph tennis correspondent on BBC Radio 5 live sports extra

"Murray v Federer is a fascinating match and it's been given extra interest this year because of the super coaches. Last year's match in the semis was a rollicking ride and ended when Federer swore at Murray across the other side of the net, which made for great copy."

BBC Radio 5 live sports extra

Serena Williams's coach Patrick Mouratoglou has given Murray a few tips on how to beat Federer on Wednesday.

"Keep him to the backhand side and play really high over Roger's shoulder and keep him long," Mouratoglou told BBC Radio 5 live sports extra.

"When he [Federer] plays under six to eight shots he has a lot of inspiration. When the rally starts to last a bit longer he starts to lose a bit of inspiration.

"And the physical side will be important too. In the past, Andy was much better than Roger in the long term but because of the back injury we don't know if Andy's at that level. We don't know which one is in the best physical shape if it's a long match."

Coverage of Andy Murray's quarter-final against Roger Federer will begin on BBC Radio 5 live sports extra at 08:00 GMT on Wednesday.

On Wednesday, we will witness the first heavyweight bout of the year when Andy Murray comes up against Roger Federer in the quarter-final.

"I would hardly call Federer stepping into the unknown," Murray's coach Ivan Lendl tells BBC Sport 5 live extra. "He has played him many times and we all know what to expect.

"I think Andy is ready to go head to head with these guys but even if you're really ready and haven't had any setbacks or injuries you still don't know what's going to happen."

Listen to Tennis Breakfast on BBC Radio 5 live sports extra

Image source, Getty Images

Bouchard had previously never made it beyond the third round of a Grand Slam but is now in the semi-finals and will come up against Li Na, a two-time finalist in this competition.

The fourth seed eased to a one-sided 6-2 6-2 victory over Italy's Flavia Pennetta.

"I've got a lot of confidence because I was match point down and I came back to win that match," said the 31-year-old. "I believe in myself even more. I hope I can take one more step this year."