World number six Jo-Wilfried Tsonga was made to work hard by number 74 Flavio Cipolla before he earned a place in the quarter-finals of the Qatar Open.
Tsonga trailed the Italian 5-3 in the first set and had to save two set points before coming through a fluctuating contest 7-6 (10-8) 6-3.
The Frenchman is determined to challenge the elite top four of Novak Djokovic, Rafael Nadal, Roger Federer and Andy Murray this year and admitted: "I have to find some new things.
"For sure I have to do that to play against the big four. I try to improve my game with something. It's difficult to be better, but I will continue to go to the net more."
Tsonga has also devised a method of ensuring he does not start too slowly - doing his warm-up routine very soon before a match begins - describing himself as "like a diesel".
"I need to be warm at the beginning, so I don't get broken early, and then it's difficult to come back," he added.
But it was Cipolla who took the initiative in the seventh game, luring the third seed into two mis-hits and a backhand drive into the net to earn a break of serve.
However, the Italian tightened up when he tried to serve for the set at 5-4, serving a double fault in the process, and in the tie-break he led 7-6 and 8-7 but could not clinch the set.
In the second set Tsonga appeared to be in control, breaking serve twice to lead 4-1.
But Cipolla pulled one break back before Tsonga immediately broke again, with two fine forehands, a deep approach and a thundering smash to finish the match.
Next up for Tsonga in the last eight is Albert Ramos, the world number 65 from Spain, who had a walkover in the last eight when Alex Bogomolov, the sixth seeded Russian, withdrew from his second round match with a right ankle injury.
Top seed Rafael Nadal is also through to the last eight after crushing German qualifier Denis Gremelmayr 6-2 6-2.
Nadal broke the 189th-ranked Gremelmayr in the first game of both sets and was never seriously threatened. The match could have been even more one-sided but Nadal managed to convert only four of 15 break points.
"I'm trying to play aggressive, I'm trying to return a little bit better, because for me the worst thing I did for most of last year was the return, especially the second half of the year," the Spaniard said.
"I'm so happy with my returns here and happy how a few things have worked well with the new weight of the racket. I'm starting to have good feelings, so that's really important."
Roger Federer joined Nadal in the quarter-finals after overwhelming Slovenian qualifier Grega Zemlja 6-2 6-3. It was the in-form Swiss star's 19th win in a row dating back to his US Open semi-final loss to Novak Djokovic.