World number two Rafael Nadal overcame a poor start to crush Frenchman Gilles Simon on day five of the Australian Open.
A quarter-finalist at Melbourne Park 12 months ago, the Spanish second seed trailed 5-2 in the opening set but proceeded to win the next nine games to set himself on the way to a 7-5 6-2 6-3 triumph.
Nadal had to dig deep in the first set, saving six set points in all in the eighth and ninth games as he rallied from the perilous position.
Simon was not able to stall Nadal's momentum until the fifth game of the second set, and the damage was done by that point as Nadal raced two sets clear and eventually won 17 of the final 22 games to set up a clash with Paul-Henri Mathieu.
Nadal was at a loss after the match to explain why he had started so slowly, especially as his normal pattern of play is to jump out of the blocks in an effort to make his opponent keep up.
'I know normally I start very hard, and today, well, I really don't know,' Nadal said. "I started the match without very good tactics, I think.
'I started the match watching the rival, not worried about me or trying to do my game, trying to play aggressive with my forehand. So that's what I have to do - not watch the other side.'
Asked about his mindset when he trailed early in the contest, Nadal said it was simply a case of trying to concentrate on his own game with the confidence he could turn things around.
'I just tried to play my game,' he added.
'I know I was not doing the things how I would like to do because I didn't play aggressive, I didn't have the control of the point.
'And I know in some moments of the match I had to change. I had to try to start playing my forehand, try to have the control of the point with my forehand, move Gilles.
'When I had that, when you do these things, the match changed a lot.'
In a see-saw battle on Show Court Three in the afternoon and early evening, 23rd seed Mathieu eventually outlasted Austrian Stefan Koubek to claim a 4-6 7-6 (7/4) 2-6 7-5 8-6 victory.
Earlier in the day, exciting French youngster Jo-Wilfried Tsonga and Russian seeds Nikolay Davydenko and Mikhail Youzhny had also booked their places in the fourth round.
Tsonga, who upset British number nine seed Andy Murray in four sets in the opening round on Monday, has backed up that surprise result with two convincing victories since, the latest a 6-3 6-4 6-2 demolition of sick Spaniard Guillermo Garcia-Lopez.
Tsonga grabbed early breaks in each of the first two sets to stamp his authority on the contest, with Garcia-Lopez requiring treatment for an illness midway through the second set.
With the first two sets already in his pocket, Tsonga then raced away with the third set in 26 minutes, with not even the only break of his serve in the set stopping him from cruising to the 103-minute triumph.
Fourth seed Davydenko had little trouble brushing aside Tsonga's countryman Marc Gicquel 6-3 6-2 6-3, setting up a fourth-round meeting with number 14 seed Youzhny.
Youzhny hit an impressive 25 winners as he broke serve five times from six chances en route to a 6-2 6-4 6-2 win, but he was also well assisted by Croatian number 20 seed Ivo Karlovic's 42 unforced errors.
Philipp Kohlschreiber downed a frustrated Andy Roddick to move into the fourth round after a titanic five-set struggle lasting until the early hours of Saturday morning in Melbourne.
German Kohlschreiber, the 29th seed, eliminated the 2003 US Open winner with a 6-4 3-6 7-6 (11/9) 6-7 (3/7) 8-6 triumph in just under four hours, finishing shortly after 2am local time.
Roddick, who launched a series of verbal assaults on chair umpire Emmanuel Joseph during the tense battle, served a career-high 42 aces.
However, Kohlschreiber himself sent down 32 winners on his serve and broke the weary American in the 14th game of the final set to secure the surprise win.
In an astonishing contest packed full of inspiring passing shots, Kohlschreiber racked up 104 winners to his opponent's 79 and his blistering backhand won him a host of key points.
He required five match points, all on Roddick's serve, before eventually securing a ticket to the next phase of the event.
The German, who reached the fourth round at Melbourne Park in 2005, will tackle 24th seed Jarkko Nieminen on Sunday for a place in the last eight of the year's opening slam.
Nieminen made it a nightmare evening for the Americans, eliminating Mardy Fish in four sets on Margaret Court Arena.
