Andy Murray next plays lucky loser Stephane Robert for a place in the quarter-finals in Melbourne.

"It's been a good start," says Andy Murray. "It was obviously tricky conditions in the first couple of days but today was beautiful. Every time I've come here, since I was 18 years old, the support has been great so thank you very much and I'll need it if I want to go further. I grew up playing with my brother, he is a leftie, so I got a lot of practice facing the leftie serve."

Jeremy Bates
Former British number one on BBC Radio 5 live

"Let's not forget Lopez is 27 in the world. Andy Murray winning in straight sets, that's pretty impressive with the lack of matches he's had. He can feel satisfied with today's efforts."

Murray seemed in trouble early on, clutching his back, grimacing and tugging his shirt at every opportunity. He went through a spell of ranting to himself, seemingly to try to get the focus back on the tennis and it worked a treat. The Wimbledon champion was ruthless in the last two thirds of the match and opened up Lopez in clinical fashion to take an 8-0 head-to-head lead against the Spaniard.

Murray puts on a show for the first two points, carving Lopez apart, but gets a bit flash with the third and pumps an overhead long. Still, he very quickly edges to two match points, and wraps it up with a second serve that has Lopez wafting the ball skywards. Murray into fourth round.

Lopez, briefly lit up by some still smouldering embers, produces a sublime game to keep the match alive. Shame his belief left him 20 minutes ago.

Murray is all energy, bristle and bounce and is playing like a man with some important function to get to quickly. He thumps down three aces to win his service game and the writing is on the door and most of the walls for Lopez.

Lopez is moving slowly between points, in contrast to Murray's newfound sparky demeanour. Murray grabs three quick break points and nails the game to edge within smelling distance of the fourth round.

FoxMulder:, external Wozniaki feeling the heat from the young tennis player... what a brilliant talent

Murray pummels the tram line on Lopez's forehand and the Spaniard gives it a long, hard Paddington Bear stare. The Scot has his serve zeroed in and races effortlessly to the hold.

Caroline Wozniacki's stint in Melbourne turned out to be a short one as the Dane, the 10th seed, has been beaten 4-6 7-5 6-2 by Spain's Garbine Muguruza. The 20-year-old, ranked 38 in the world, went for broke against the former world number one, hitting 33 winners and 56 unforced errors, and it worked.

Image source, Getty Images

Results from the women's third round

Image source, AP

Lopez cuts a slightly dejected figure as he half-heartedly challenges a ball on the base line. Turns out it is good and he trousers an unlikely point. A hefty whack from the service line gives him 40-15 but Murray punishes the next serve with a fiery backhand return before Lopez holds.

Lopez must be sick of the sight of this net as Murray edges to 40-15, but it is swings and roundabouts as a net cord digs him out of trouble. Murray closes out the game to consolidate his break.

A blue shirt to match the shorts for this set from Murray. And as with the last change of kit, he loses the first point. Lopez, his arms held together by sweat bands, is quickly on the back foot and a deft chipped Murray backhand takes him to game point, which he seals.

Latest men's scores from day four in Melbourne

Men's results

An absorbing 18-shot rally but it is Murray who blinks first and sticks one in the net for 15-15. A double-handed backhand crosscourt is called wide and Murray challenges but it is out and Lopez gets a nose in front. Another cracking rally ends with a brilliant Murray return and a net from Lopez and a big serve gives Murray a point for the second set. After a long exchange, Lopez challenges a call but the ball is ruled out and Murray clinches the second set.

Image source, Reuters

A couple of wayward ones from Murray and Lopez is quickly at 40-0 before he pulls out a double fault - his seventh - at just the wrong moment. But he holds with the next point leaving Murray to serve for a two sets to love lead.

Murray kicks off with only his second ace of the match at 198kmph and soon clinches the game to 15. Looking very untroubled on his own serve now.

Lopez in command in this game, moving Murray around at will, and he holds easily. The ebbs and flows in tennis are endlessly fascinating.

Jeremy Bates
Former British number one on BBC Radio 5 live

"Lopez has this long, flowing technique on the serve. He has long levers when he's hitting the ball and when the timing is on, and when he gets inspired, he can generate an enormous amount of strength and it's a question of Murray keeping him down all the time. He is somebody you need to dominate and keep on top of because he's very dangerous when he finds the groove."

Listen to live commentary on BBC Radio 5 live