Tamsyn Ellwood:, external Not even sure who I want to win but what a great game. Working a night shift tonight so need some sleep soon please.

The defending champion will not be bowing out on his own serve. Not in this game anyway. Aggressive serving from Djokovic who throws an ace into what some people would call the mixer during an impressive hold to love.

Sixteen aces have pinged from Wawrinka's racquet during this match. Impressive stuff from the Swiss and a backhand return goes long from Djokovic for a hold to love. The defending champion serving to stay in this match. Cue roars.

The final set between these two gunslingers ended 12-10 in Djokovic's favour last year so there will perhaps still be time to fetch a fresh supply of nibbles. Some biscuits maybe because it's nearing lunchtime after all? A hold to 30 for Djokovic. Becker on his feet, glaring down at the canvas, hoping his man can come up with the killer blow.

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

Image source, Reuters

"What a time of the match to serve your biggest serve of the night. That's pure adrenaline. He's really drawing on his extreme reserves now but he's still finding the power when he needs it. Djokovic keeps getting these opportunities but can't quite get the break he wants."

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Djokovic threads a crunching backhand winner down the line and Wawrinka is forced to look on in admiration like the rest of us. From 15-15 to 40-15 as Wawrinka matches Djokovic when it comes to backhand magic. But the Swiss going in search of winners when patience is required and drags a backhand into the tramline for deuce.

The Swiss pulls Djokovic from tramline to tramline and bravely goes for the forehand winner which Djokovic merely nets. A couple of flaky forehands, though, earns Djokovic a break point. Ace down the middle and if I were a cowboy I'd say yeehaw, but I'm not. Deuce. Ace. Advantage. Sharp-shooting from Wawrinka under the glare of the floodlights and the eighth seed starting to enjoy himself on this grand stage. Loose-limbed hitting from the baseline until Djokovic goes long.

Piers Newbery
BBC Sport at Melbourne Park

"Djokovic emits a roar and Becker, who has had the look of a Premier League manager flirting with the relegation zone for the last hour, unleashes the double fist-pump, before reverting to a Lendl-like poise. It's hard to think Wawrinka won't have his last two grand slam meetings with Djokovic in his mind right now."

An ace out wide eases Djokovic to 40-0 and an ill-judged drop shot from Wawrinka allows the Serb to level.

Image source, AFP

This match is now into its fourth hour and momentum is moving this way and that. The forehand is troubling Djokovic but at 30-30 he's hanging onto Wawrinka's coattails and, out of nothing, the Serb has break point as Wawrinka's forehand bounces long. How will Wawrinka respond? Coolly, nervelessly. Another wacky rally ensures 28 shots.. 29 shots... on and on we go...30 shots... and then Djokovic forehand falters. The longest rally of the match ends after 31 shots. Wawrinka puts daylight between himself and Djokovic at advantage and unleashes a thumping ace.

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

"This is totally unprecedented. Djokovic is not feeling the ball, he's not moving his feet and that was a very weary forehand at the end of that game. He's been fighting himself, trying to get some feel, all evening and then having got the break of serve he just relaxed. That was a cheap game. Very uncharacteristic from Djokovic."

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"Come on," shouts Wawrinka who sniffs a chance as Djokovic plonks a straightforward forehand into the tape, allowing the Swiss to eke a 0-30 lead. It's the Swiss flags which are being waved proudly as Wawrinka collects two break points thanks to another wayward Djokovic forehand. The Serb's feet not moving in unison and another clumsy forehand into the tape lets Wawrinka back into this match.

Djokovic content to fetch and retrieve all day long and comes out on top of a 20-shot slug-fest with Wawrinka netting a forehand. The rubber-legged Serb offering a wall-like resistance at the baseline, forcing Wawrinka once again to biff a forehand long and he's back in contention at 30-30.

A monstrous first serve, though, sets up Wawrinka for a crisp volley for 40-30 but he throws in a double fault. Deuce. Becker impersonating Sir Alex Ferguson, manically chewing gum on the sidelines.

Agonising for Wawrinka, pushing a volley into the tramlines when Djokovic was beaten. Break point. Another lengthy rally... hearts beating faster... A pin-point forehand into the corner from Djokovic... Wawrinka forced to scamper out to the wings and nets a forehand.

Djokovic mirroring Wawrinka's efforts in this final set, collecting three points easily. The Swiss ruins what would have been a blemish free service game, but Djokovic eventually holds to 15, sending the Swiss scampering along the baseline with Wawrinka unable to negotiate the barrier.

Wawrinka gets the final set under way and the Swiss serving like a cucumber which has been wrapped in an ice pack and spent the night in a freezer. Booming serve after booming serve and he holds to love.

BBC Tennis:, external Twelve months ago David Law and Jeremy Bates commentated on a Djokovic/Wawrinka classic. Here we go again.

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

"What an incredible response from Djokovic to close that set out with an ace. What a shift in momentum. Wawrinka was doubting himself in the closing stages. He played the right tactics in sets two and three but his first serve is crucial and that faltered slightly in the fourth set."

At 30-30, Djokovic screws a forehand wide. He shakes his head, challenges, but is unsuccessful. Break point Wawrinka. This plot has a few more twists and turns before the final chapter. Wawrinka's backhand falters and Djokovic is demanding more urgency from the ballboy, asking him to hurry with the towel.

The Serb perhaps needs to cool down as a series of crunching forehands has Djokovic rocking. Second break point. An ace gets the Serb out of trouble and Djokovic lets out a primeval roar. Danger averted and then Wawrinka's backhand sails long. Becker applauding. Djokovic within a point. An ace seals the deal. We're into a fifth, but deep down we knew we would be. It always is with these two.

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

"Amazing agility from Djokovic to drag that return back into the corner. Maybe that's the turning point we were talking about. Djokovic has a new lease of life."

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Wawrinka has had to come through a few sticky moments on his own serve in this set but seems Djokovic is helpless, spraying his returns long and wide, as he watches his rival skip off into the distance to a 40-0 lead. But, even with Wawrinka merely a speck in the distance, the Serb is unwilling to give up the fight and he pumps and snorts his way to deuce, drawing level with his opponent as they prepare to gallop down the home straight.

Marvellous from Djokovic. Incredible. A Shane Warne-like spin on the forehand return and it drops in. Break point. Wawrinka folds like a deckchair in the wind. Deafening roars. Wow.

A Djokovic fan can be seen waving a Serbian flag in the air and he, like the rest of us, perhaps sensing we're in for the long haul. The second seed serving with ease, a hold to 15 in fact.