World number two Roger Federer had one foot in the grave before rediscovering his touch to down Germany's Tommy Haas 6-7, 5-7, 6-4, 6-0, 6-2 and reach the quarter-finals of the French Open on Monday.
The 27-year-old Swiss, chasing the only Grand Slam title to have eluded him, was two sets and 3-4 down facing a break point when he recovered to hold serve and went on to win eight games in a row.
"Tommy played a great match, I struggled to get into the encounter," said the 13-times Grand Slam champion.
"When I hit that forehand to save a break point at 3-4 in the third, I had the feeling it could be a turning point in the match.
"After that, the atmosphere was great."
He broke in the fifth and seventh games of the decider and never looked back, wrapping up victory on his second match point after three hours seven minutes.
Federer, hot favourite to win the title after world number one and four-times champion Rafael Nadal was beaten on Sunday, will next face either France's Gael Monfils or American Andy Roddick.
Asked who he would like to face, Federer grinned: "I'm 18-2 against Roddick so you can imagine who."
