PARIS -- French Open marathon man Albert Costa dug another big hole in the red clay of Roland Garros, and again found his way out.

The defending champion erased a two-set deficit for the third time in five matches Wednesday, wearing down Tommy Robredo for an improbable quarterfinal victory, 2-6, 3-6, 6-4, 7-5, 6-2.

When Costa beat Sergio Roitman in the opening round after losing the first two sets, it was the first such comeback in the Spaniard's 10-year career. Then he did it again in the third round against Nicolas Lapentti.

"I promise it's not a strategy,'' Costa said. "When I am two sets down, I still think I can win the match. I don't know why.''

Comeback Costa also won a five-setter in the second round. He has played 23 sets and 227 games totaling 18 hours, 31 minutes to reach the semifinals.

Costa is the first player in the Open era to win four five-set matches in a single French Open. The only other player to overcome a two-set deficit three times in a Grand Slam tournament was Nicolas Escude at the 1998 Australian Open.

Leaving the court after 3:29 of high-wire tennis Wednesday, Costa was told he didn't even look tired.

"Maybe it's the smile,'' he said. "But I am tired, very tired.''

He needs two more wins for a second consecutive French Open title. It would also be his second title in the past 89 tournaments.

Costa's opponent Friday will be the winner of Wednesday's late match between Juan Carlos Ferrero and Fernando Gonzalez.

After trailing the No. 28-seeded Robredo for most of the match, the ninth-seeded Costa won the final five games. A backhand volley winner on match point gave Costa the victory, and he fell on his back with a scream of jubilation.

"The only thing I tried to do was to continue and to think I could still do it,'' he said. "Why not repeat the same success if my body allows it?''

Robredo was trying to upset a Grand Slam champion for the third match in a row. He beat top-ranked Lleyton Hewitt in the third round and three-time French Open champion Gustavo Kuerten in the fourth round.

He dominated the first two sets against Costa, but the defending champion then changed tactics. Instead of trying to rally from 6 feet behind the baseline, he tried to take balls early to shorten the points.

The strategy worked, and as the match approached three hours, Robredo was obviously the wearier player. He dallied during changeovers and failed to reach shots he chased down earlier.

When Costa reeled him in with a drop shot and then lobbed a winner over his head, a frustrated Robredo gave his racket an overhead heave toward the backstop. Four points later, Costa took the lead for the first time -- and for good -- when Robredo double-faulted to make it 3-2 in the final set.

Costa struggled with his serve early, then lost just one point in his final five service games.

"Anything can happen, no?'' Robredo said. "What he did today -- it's very difficult.''

The match was big news in Spain, but it began with the center-court stands half empty, and the crowd was subdued for much of the marathon. Costa dropped his first three service games, and Robredo hit 17 winners in the opening set.

Costa lost serve twice more in the second set, including in the final game with a double-fault on break point.

Robredo broke again for a 2-0 lead in the fourth set, but then showed signs of nerves for the first time, and his mood didn't improve when he argued at length after the umpire ordered a point replayed.

Costa broke back, then broke twice more. He held at love to close the set and force yet another fifth set.

"This is an experience I have to learn from,'' Robredo said. "Perhaps one day I'll be able to respond the way he does.''