Third seed Novak Djokovic reached his second straight quarter-final at the Rome Masters on Thursday, winning a battle of nearly three hours with Igor Andreev 6-3, 3-6, 6-3.
The victory improved the Serbian's record against the Russian to 4-0 after two wins in 2007 on clay and a Dubai quarter-final this March, dpa reported.
"He's a tough player, especially on clay," said Djokovic, who saved nine of the 11 break points he faced. "That's where he plays his best tennis.
"It was a battle and I'm very happy to have won it."
Djokovic, whose stamina has long been suspect, is playing for the first time since quitting a Monte Carlo semi-final against Roger Federer last month complaining of a sore throat.
The Serb also took a swat at Rome organisers this week over what he said was the slippery state of the showcourt.
His fitness will face a Friday test as he goes against Spaniard Nicolas Almagro, who advanced without lifting a racket after 2007 finalist Fernando Gonzalez withdrew before their third-round contest with an adductor injury.
"I have one match more than him, but physically I'll have to recover quickly," said Australian Open winner Djokovic.
Djokovic was unable to close out a straight-sets win over the 26th-ranked Andreev as the Russian secured a second-set break on his fourth opportunity of the fourth game.
In the third set, the seed re-established his momentum with a 5-2 margin and served out victory two games later.
Top seed Roger Federer was bidding for the last eight as he faced Croatian Ivo Karlovic later.