Argentina's David Nalbandian has become the fourth Argentine to reach this year's French Open quarter-finals by ousting dogged Russian Marat Safin 7-5 6-4 6-7 6-3.
Eighth seed Nalbandian, the 2002 Wimbledon runner-up, will play three-times former French Open champion Gustavo Kuerten of Brazil in the last eight.
His victory, sealed with an ace, means he joins compatriot and third seed Guillermo Coria, Juan Ignacio Chela and Gaston Gaudio in the last sixteen.
Safin needed courtside treatment for hand blisters throughout the match as an eventful first week, in which he won two five-set thrillers and was sanctioned for pulling his shorts down on court, finally caught up with him.
The 24-year-old Russian, who missed most of last season with a wrist problem, finished the match with plasters on three left fingers, his left and right palms and he also had two fingers on his right hand strapped together.
Safin had won all four of their previous encounters but the Argentine took the first two sets by raising his game when it mattered.
Nalbandian, who reached the quarter-finals of the Australian Open this year and in 2003 and the U.S. Open semi-finals last year, sealed the first set with a second service ace having broken for 6-5.
The powerful 22-year-old Argentine also won the second set with an ace and looked the likelier victor in the third until a dramatic tie-break.
Nalbandian led 3-0 but serving at 5-4 he fatally misjudged a Safin service return, allowing it to drop on the baseline.
Safin rubbed salt into the wound with a cheeky drop shot retrieve on the next point and when Nalbandian netted a forehand return, the Russian had won himself the set to the delight of the Roland Garros crowd.
The reprieve was short-lived, however. Safin's hands were causing him severe discomfort and he quickly went 3-0 down in the fourth set. At 1-3, 30-30 he stomped back to his chair for more treatment, hurling his racket down in frustration.
Nalbandian duly completed his victory, serving out to love before gingerly shaking the hand of the suffering Russian.