A rare baseline tussle... Djokovic dragging Raonic towards the tape with a drop shot... Djokovic with the lob, but Raonic stretches his 6ft 5in frame to send an overhead beyond the world number one. Raonic is far from convincing and is continuing to cough and splutter at the net, but he holds on to Djokovic's coattails by his fingertips with a hold to 30.

Joe@Rocket:, external Djokovic once again playing very calm yet extremely ruthless tennis. It's easy to understand why Raonic is struggling to catch up.

Should Djokovic win this match in straight sets, it would be the first time since 2008 that the Serb has advanced to the semi-finals at the Australian Open without dropping a set. At this moment, Raonic would just be happy to win a point. Another hold to love for Djokovic in another snappy service game.

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The Raonic serve back on song, but is it all too late for the Canadian in this set? The young pretender holds to love, but returns to his seat for the changeover with the look of a man whose hopes are already whistling in the Melbourne wind.

Djokovic the superior player at the beginning of this second set. The Serb making few errors and serving with aplomb. Raonic moving with the grace of an oil tanker at the net and it's no surprise that he pushes a volley into the tramlines, gifting Djokovic another simple hold.

Simon Richardson:, external Obviously it isn't his fault, but I find it hard to wish success upon Raonic when he is so obviously just a serve and little else.

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Those who predicted Raonic was about to sink without a trace were exaggerating. The Canadian still launching bullets from the service line, which eases him to 40-0. Djokovic nicks a point, but can do no better than that and the 24-year-old returns to his seat to wipe his sweaty brow with a game in the bag.

Leon Smith
BBC Radio 5 live sports extra analyst and GB Davis Cup captain

"Now Raonic is playing catch up and it will be pretty difficult. It's ruthless tennis from Djokovic. He will now have one eye on the next match - it's that killer instinct. He won't want to hang around here, he'll just want to move on."

Djokovic oozing confidence, giving Raonic little chance on his serve. Rat-a-tat-tat. A hold to love and the pressure mounts on the young Canadian.

What's that? That's the sound of screeching violins as Raonic produces a horror of a game, presenting Djokovic with three break points. Hold your ears, look away, Anthony Perkins is about to make an appearance... Raonic saves one but can do little to prevent Djokovic breaking with a brilliant passing forehand.

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From 4-2 to 4-3 before Djokovic produces his fifth ace of the match - that one a brave howitzer down the middle for a 5-3 lead. The Serb pulling his opponent this way and that before coming to the net and beating the flat-footed Raonic with a deep volley. Three set points... Djokovic thinks he's won it - but replays show Raonic's looping volley kissed the tramline. An intake of breath from the crowd once they realise how close that was. The pair trade missiles from the baseline and another set point disappears as Djokovic goes long on the forehand. Oof the tension. But on the next point Raonic swings wildly on his forehand and the first set belongs to his opponent.

Djokovic grunting and groaning as he tries to outdo Raonic from the baseline...15 shots, 16 shots... 17 shots and Raonic crumbles, drilling a backhand into the tape. 1-0 Djokovic. The Serb targeting the Raonic backhand and it's a wise ploy as the Canadian's effort drifts over the baseline. An ace reduces the deficit to 2-1, and Raonic is level again as a floundering Djokovic slaps a forehand into the tape.

Zany angles from the baseline, Djokovic calling the shots and Raonic with a tired-looking forehand into the tape. Another iffy forehand from Raonic and the top seed is 4-2 up at the changeover.

Raonic is bidding to become the first Canadian man in history to reach the Australian Open semi-finals and he's doing his best to create history. Three super-duper aces in a love hold game. Anyone for a tie-break?

David Law
BBC Radio 5 live sports extra commentator

"The obvious view would be that Milos Raonic needs to take this into tie-breaks. But Novak Djokovic has won three of the four tie-breaks they've played."

The crowd rooting for the underdog, cheering Raonic as he skips towards the tape and pings an overhead beyond Djokovic. But even though Djokovic is not at his best, he continues to hold with ease - an ace out wide ends the game in the Serb's favour.

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Djokovic the master returner failing from the back of the court as Raonic fires an overhead his way. But Raonic coughs up a double fault to give the Serb a chance at 30-30. An uncharacteristic error from Djokovic, though, as he screws a crosscourt backhand long and sloppy errors from the top seed allow Raonic to hold without much fuss.

The longer the rally the more likely Djokovic is to win the point. The Serb coming out on top of the baseline battles, but also throwing an ace or two into the mix. There's not even the merest sniff of a whiff in this game that Raonic will trouble the Djokovic serve.

Leon Smith
BBC Radio 5 live sports extra analyst & GB Davis Cup captain

"Once again, we see the benefits of having a monster serve, with Raonic throwing in a couple over 140mph. On the last point, it was interesting to see him targeting Djokovic's forehand and beating him for power."

Image source, Reuters

Raonic slaps a straightforward volley into the net when the court was at his mercy and the oohing crowd feel his anguish. The Raonic forehand faltering as he forsakes power for precision and Djokovic has a break point. Twelve unforced errors from Raonic's unpredictable racquet. But a 142mph serve - his equal fastest of the tournament - full of menace and spin gets him out of trouble.

Djokovic with the speed of a cobra's tongue at deuce, racing towards the tape to pounce on a Raonic volley and reply with a canny crosscourt volley. A fist pump from Boris Becker, but it's an opportunity wasted for the Serb as Raonic serves his way out of danger.

Alex Haworth:, external I'm tempted to say already that Djokovic will win 6-3, 6-4, 6-4. Similar to Raonic-Federer at Wimbledon.