Second seed Maria Sharapova plays 31st seed Zarina Diyas at 08:00 GMT for a place in the last 16. That match will be followed by third seed Rafael Nadal v unseeded Dudi Sela. And I'm pleased to say we will have live text commentary on both those matches coming up shortly. That's it from me, though, so until next time, it's good morning from me. See ya!
- Roger Federer out of Australian Open
- Federer beaten by Andreas Seppi in four sets
- Andy Murray beats Joao Sousa 6-1 6-1 7-5
- The Scot will play Grigor Dimitrov in the last 16
Well, no one saw a Roger Federer defeat coming did they? The Swiss, who last won the Australian Open 2010, must wait another year. His last Grand Slam title came back in 2012. Will there be more drama later on today when Maria Sharapova and Rafael Nadal are in action in the evening session?
"I just tried to enjoy playing on centre court again," said Seppi after his shock win over Federer. "It's not often you get the chance to play on centre court.
"I just tried to play my best and I did because I was playing Roger. You never feel comfortable playing against Roger, but I was focussing on my service game, I didn't have many chances on his serve."
Earlier in the day, 10th seed Grigor Dimitrov outlasted former finalist Marcos Baghdatis over five sets to set up a last 16 match against Andy Murray at the Australian Open.
Andreas Seppi's reward for victory over Roger Federer is a meeting with either Malek Jaziri or Nick Kyrgios in the last 16.
Roger Federer, a 17-time Grand Slam champion, has not lost this early at the Australian Open since 2000, the second year he played here. It is also the unseeded Seppi's first win against Federer in 11 attempts.
Seppi conjures up a beautiful forehand winner to bring up match point. Is it all over for another year for Federer? Yes it is! Seppi pulls out a forehand from the very top drawer, while on the stretch I should add, to pass Federer at the net and secure an unlikely victory. As ever, Federer is gracious in defeat.
Oh the tension! Federer secures a mini-break with a backhand winner, but then throws it away with a backhand error in the next. At 5-5, the Swiss is now just two points from defeat.
We're straight over to the Rod Laver Arena where Roger Federer is on the verge of getting dumped out of this year's Australian Open. The Swiss lost the first two sets to Andreas Seppi but hit back to win the third. We're in a fourth set tie-break, with the pair locked at 4-4.
Murray will play Grigor Dimitrov in the last 16, the Scot aiming to amend for last summer's Wimbledon defeat by the Bulgarian when they meet on Sunday. The Bulgarian 10th seed needed five sets to get past Marcos Baghdatis earlier today.
"I was up two sets and 4-1, but he got back into it," says Murray. "He competed very well. He always does and made it difficult in the end, but it was a good match.
"I'm feeling pretty good so far. I have played three quite quick matches which helps, but you expect the matches to get a little tougher as you go through each round so if you can conserve energy, that's always good."
Better from Murray in the first point, the Scot's aggressive play earning him the first point. But he hits too short in the next and Sousa whips the ball away for a winner.
The pendulum swings the other way as Murray somehow guides the ball back into court, when stretching on the run for 15-30, but Sousa responds well to level again.
Murray brings up match point. Sousa hits long, but is it long? Sousa wants to challenge, the Portuguese arguing with the umpire. But he eventually concedes and offers his hand to Murray. Victory, then, for the world number six but boy did he make it hard for himself in that final set.
Much better game from Murray, who flies through his service game to love in under a minute. That'll ease the frustration and quickly heaps the pressure onto Sousa, who will once again serve to stay in the match.
With a shadow now looming over most of the court, Murray chooses to ditch his baseball cap. The wardrobe tweak seems to help as he soon finds himself with two match points. Sousa saves the first with a forehand volley winner and is then relieved to see Murray dump a forehand in the net. Deuce.
Murray's frustration is clear, the Scot muttering to himself between points as he tightens up. A forehand sails long to gift Sousa game point. But back comes Murray, putting Sousa on the run and nailing a good passing shot which the Portuguese can't keep in play. Deuce.
Sousa punches the air and gives a glare up to his box as he wins the next two points to seal the game. On we go...
Roger Federer is serving to stay in the tournament over on the Rod Laver Arena.
The four-time champion is 5-4 down in the fourth set against Italian Andreas Seppi, who leads by two sets to one.
Better from Murray, who finds his range again and motors to a 40-0 lead. But it's clear that the Scot is getting a bit tentative and Sousa takes advantage, winning the next two points. Danger averted in the next, as Murray fires a backhand down the line to move 5-4 clear and Sousa will now serve to stay in the match.
Sousa has found something from somewhere and it's Murray who is now doing all the scrambling. And out of nowhere, we're level in the third set as Sousa holds to 15.
Murray looked to be cruising at 40-15, but he throws in a double fault and a tame forehand and suddenly we're at deuce. Sousa takes advantage of Murray's dip in form, bringing up only his second break point of the match with some aggressive play. And would you believe it? Sousa breaks as Murray frames a forehand! The Scot throws his racquet down in frustration. We're back on serve.
The crowd erupts as Murray pulls off a sensational shot played through his legs, but Sousa is waiting at the net to put away the winner. The Portuguese carries the momentum to win his service game to love. That's only his fourth game of the match.
Sam Barker: "This is a clinical Andy Murray, the likes of I can't remember having seen for a number of years. Coaching changes paying off." Aidan Williams: "Murray looks like he's coaching Sousa. It doesn't even look like a competition."Paul Collins: "Come on @andy_murray. He can win this Australian Open. Only Djokovic to really fear."
Murray is racing towards the fourth round as he seals another love service game.
Murray brings up two break points and you sense that if he converts one of them, there will be no way back for Sousa. Murray misses out on the first one, as Sousa puts away a smash, but he takes the next with a scintillating backhand winner. The Scot is now just three games away from victory.
Four-time Australian Open Roger Federer is back in the game on Rod Laver Arena.
The Swiss has taken the third set 6-4 and now trails 2-1 in sets against unheralded Italian Andreas Seppi.
It's a clinical service game from Murray who sails through to love.
BBC Sport at Melbourne Park
"Sharapova, Nadal, now Federer…. some of the the biggest names have struggled at times this week in what is turning out to be a memorable first week. Federer looks to be on the way back against Seppi but a whopping 38 unforced errors has even the Swiss press here doubting whether their man can get out of this one. The question is whether Seppi, with a 0-10 record against the great man, believes he can finish the job."
BBC tennis correspondent on Radio 5 live sports extra
"Murray has only dropped two games so far and is two sets to the good. Latest tribute song from his 'choir' is to the tune of 'The lion sleeps tonight'."
It's like a training match for Murray out on Hisense, the Scot playing well within himself. Even when he's put on the stretch, which has rarely happened today, Murray has the answer, firing a backhand cross-court pass back to bring up break point. Sousa saves it to force deuce and the Portuguese's brave defence is rewarded with a game.
It's a change of colours for Sousa, who swaps his fluorescent green top for a white ensemble. It makes no difference to the flow of the match, though, as Murray races through his service game to 15, closing it out with an ace.
Murray's coach Amelie Mauresmo looks very relaxed in the stands - and so she should be as her man is demolishing his opponent out on Hisense. Two loose forehands from Sousa gift Murray set point but the Scot touches the net, which is a foul, as he races to reach a drop shot and we're at deuce.
Murray cranks up the forehand, unleashing one down the line before picking off the return with a cross-court winner to bring up another set point. This time, Murray takes it as Sousa dumps a forehand in the net. This match could be over very soon.
Murray's fifth ace of the match seals his service game to 15 and Sousa will now serve to stay in the set.
While Sousa receives treatment, here is what is happening elsewhere. Third seed Simona Halep has beaten Bethanie Mattek-Sands 6-4 7-5 while over on Rod Laver Arena, Roger Federer leads 2-1 with a break in the third set of his match against Andreas Seppi. However, Seppi leads by two sets to love.
Sousa has called the trainer. It looks like a problem with his left knee. Murray, meanwhile, is up off his chair and bouncing around during the medical time-out.
It's just sensational ball-striking from Murray, who has hit 20 winners to Sousa's nine. The Portuguese world number 55 is doing everything he can to stay in the rallies, but he's struggling to generate any depth on his groundstrokes and Murray is just swotting him away at will. The Scot breaks again.
Murray's first serve percentage has been poor, but the rest of his game is looking supreme and he consolidates the break to love.
Roger Federer is in a whole heap of trouble over on Rod Laver Arena.
The four-time champion loses a tie-break 7-5 in the second set and trails 2-0 against Italian Andreas Seppi (pictured).
Murray on the attack from the off, the Scot seizing on a lose ball and whipping it away down the line. Nonchalant.
But back comes Sousa, the Portuguese winning a 19-shot rally to bring up two game points. The first goes wanting as he dumps a regulation forehand in the net and another error, this time on the backhand flank, brings up deuce.
Another game point disappears. Deuce again. Murray rustles up a break point, but it's his turn to make an error, sending a forehand agonisingly wide. Deuce.
Sousa wastes two more game points before Murray gets his second break point. This time, he takes it as Sousa's resistance falters. The Scot is cruising.
BBC Radio 5 live sports extra commentator
"The only thing that is not working for Andy Murray at the moment is his first serve - it's not consistent enough."
Sousa snatches at a few forehands and before he knows it, Murray has raced away with the game. The Scot is well and truly in control on Hisense.