At 15-30, Raonic has a sniff. The Canadian steps in, wallops a forehand over the net but the line judge bellows "OUT!". But was it? Yep, but only by the tip of a fingernail. That was close.

From 30-30 to 40-30. A momentum-changing forehand from Raonic forces Djokovic to balloon a forehand long. A shake of the head from the world number one. Tut tut. To deuce we go. Raonic swinging loose and free from the baseline, but the Djokovic forehand pulls the top seed through.

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Raonic proving that there's more to his game than a brutal serve. The 24-year-old moves Djokovic out wide before beating him with a threaded forehand winner down the line. The Canadian follows up with a cute volley at an irretrievable angle before proceeding to mix guile with brute force as he overpowers Djokovic with his trademark booming serves.

Both players content to trade blows from the baseline. Raonic returning the Djokovic serves, but folding like a deckchair in the wind in the baseline rallies. Another straightforward hold for the former champion.

Image source, Reuters

Spectators still making their way to their seats which halts play slightly, but their late arrival doesn't distract Raonic as the Canadian fires down an ace to start the game as he means to go along. Straightforward for Raonic, holding to love in a game which had two aces. Permission to say Boom.

The winner of this match will play defending champion Stan Wawrinka. The Swiss' coach Magnus Norman is delighted with his pupil's performance in this tournament, tweeting:, external "Wow!! Just so proud to be working with this amazing player!! Great start to the year!"

A comfortable hold to 15 for Djokovic, who returns to his seat at the changeover having exerted very little energy during his quick-fire service games.

Gasps from the crowd as Raonic launches his first ace of the match, a boomer down the middle which Djokvoic wouldn't have been able to fetch had he started running for it yesterday. But Raonic needs a better all-round game if he is to trouble the top seed. He falters at the net and Djokovic responds with a well-timed lob over the towering Canadian.

Raonic battles to 30-30, but a baseline tussle ends in a netted forehand and Djokovic earns his first break point. Danger averted, though. Raonic with a missile out to the wings.

Deuce. Advantage. Deuce. Fine returning from Djokovic and the Serb has a second break point... Another ace from the eighth seed. And another. Raonic ends with a winning forehand, bringing a lengthy game to an end.

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

"It's an interesting match-up, Novak is favourite purely because of the way he returns. But Raonic has a huge serve and if he serves well, he'll have a chance."

It's so quiet on Rod Laver Arena you could probably hear a spectator blink, but there's a ripple of applause as Djokovic opens with an ace to the wings. Faulty returning from Raonic, the Canadian's feet not quite moving in unison yet, and the top seed finishes a hold to love with a crunching forehand into the corner. Easy peasy.

BBC Radio 5 live sports extra

Former top three player Ivan Ljubicic, who coaches Milos Raonic, speaking to BBC Radio 5 live sports extra: "Milos has to use his strengths, he has to serve well, be aggressive and hit his forehands. He needs to keep Novak off balance and not get involved in long rallies. He has to do his stuff really well. Novak has no weaknesses, no gaps in his game - but he is beatable."

The players are nearing the end of their warm-up, a family is taking a selfie in the crowd, while someone else is tucking into a big sarnie. But what we want to know is can anyone stop Djokovic? What's been your highlight of the tournament so far? Any other business?

Send us your chit-chat and musings by tweeting #bbctennis, external or texting 81111.

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First round: beat Aljaz Bedene (SLO) 6-3 6-2 6-4

Second round: beat Andrey Kuznetsov (RUS) 6-0 6-1 6-4

Third round: beat Fernando Verdasco (ESP) 7-6 (8-6) 6-3 6-4

Fourth round: beat Gilles Muller (LUX) 6-4 7-5 7-5

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First round: beat Illya Marchenko (UKR) 7-6 (7-3) 7-6 (7-3) 6-3

Second round: beat Donald Young (USA) 6-4 7-6 (7-3) 6-3

Third round: beat Benjamin Becker (GER) 6-4 6-3 6-3

Fourth round: beat Feliciano Lopez (ESP) 6-4 4-6 6-3 6-7 (7-9) 6-3

Image source, BBC Sport

Victory against Milos Raonic would put Djokovic one semi-final shy of Andre Agassi's record of 26 Grand Slam semi-finals, a feat the American achieved over a 20-year career on Tour, while Djokovic has accumulated his stats in just 11 years.

Raonic regards top seed Djokovic as a mentor, with the pair often practising together when the Canadian was trying to make a breakthrough in the men's game.

"I remember from a young age when I was getting and hoping for wildcards to get into the Canadian Open because my ranking wasn't high enough, I would practise with him and he would have kind words to me and my father," the eighth seed said in the build-up to this match. , external

Only three years separate Djokovic and Raonic, but in terms of experience and titles the gulf between the Canadian and the Serb is vast.

"He excelled at a young age," says Raonic of his opponent. "I was a late bloomer. I did catch up at 19-20, but I didn't do well as a junior like he did. The gap might only be three or four years in age, but it's bigger because of what points we really broke out at. He gave me a lot of great advice."

Raonic came through a five-setter against Feliciano Lopez to reach the last eight and was still launching colossal serves in the Spaniard's direction at the very end, which suggests he now has the mental and physical strength to accompany his big serves.

But in the four matches he has played Djokovic, Raonic has only won a single set. If the Montenegrin-born Canadian wants to become the "greatest player in the world" those are figures he must rebalance.

Image source, EPA

So, it's the establishment versus the new wave, the been-there-and-done-that man versus the player who wants to prove he's the real deal. Raonic has shed some pounds to improve his endurance and has hit 99 aces so far in this tournament - but has he enough skill and know-how to beat one of the game's greats on his favourite court?

Hello! Welcome to live text commentary of the quarter-final skirmish between 27-year-old Novak Djokovic and 24-year-old Milos Raonic. If you didn't know already, let me tell you that this is the first Grand Slam in over three years where there are no male players aged 30 or over through to the quarter-finals.

The average age of the quarter-finalist is 26 which, by the way, is the age Bjorn Borg retired from the sport. Those facts aren't worth getting particularly excited about but, you know, I've put it out there.

What happened to the thirtysomethings? Where are those evergreen players on the wrong side of 30 proving that age is no barrier to success on the court? Roger Federer? Gone. David Ferrer? Gone. Lleyton Hewitt? Gone. All at home, wearing their comfortable slippers and smoking jackets, examining their pension pots while watching the conclusion of a tournament where youth has prevailed.

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