covered with red dirt, engaging in gruelling baseline rallies under a hot sun.

And winning.

But down a set and 2-0 down in the second against Ecuador's Nicolas Lapentti, Rafter battled back to grind out a 4-6, 7-5, 6-1 victory yesterday in the Italian Open quarter-finals.

The serve-and-volleyer reached his first semi-final since October, following a second straight US Open, and kept alive a bid to take over the number ranking.

"It's a big surprise for me. You have all the top guys here, and I came in with very little form,'' said Rafter, loser of two consecutive opening-round matches before Rome.

"I don't know why it's happening this week.'' On a day when his punishing serve was merely average (four aces), the Australian succeeded by wearing down Lapentti, who played way above his number 32 ranking for the first hour.

Rafter gets another stern test today against 15th seed Felix Mantilla. The Spaniard advanced with a 6-2, 6-4 victory over German qualifier David Prinosil. Mantilla's eight career titles all have come on clay.

On the other half of the draw, third seed Alex Corretja of Spain overhauled unseeded Argentine Franco Squillari 5-7, 7-6 (7-4), 7-5. Squillari squandered a match point when serving at 5-4 in the second set, clubbing a forehand into the net to end a 33-stroke rally.

Gustavo Kuerten, the 1997 French Open champion, faced 10th seed Karol Kucera for the last semi-final berth.

Rafter, ranked fourth, can climb into the top spot if he wins the $2.4 million event. Current number one Yevgeny Kafelnikov was eliminated in the third round.

Rafter showed tremendous patience against Lapentti, staying back until presented with the right chance to bull-rush the net.

"So far, the clay has been good for me. Many years in the past it hasn't been,'' said Rafter, a surprise semi-finalist at the French Open two years ago but yet to win a clay title. "I'm just enjoying every match, because you never know how long it's going to last.'' It didn't look like yesterday's encounter would last long. Lapentti got to everything, put returns of serve at Rafter's ankles, and rifled passing shots seemingly at will.

But the match's complexion shifted when Lapentti had three break points to go up 3-0 in the second set. Rafter used an ace and two service winners to stay alive. "That would have been another kick in the head. That was one point that made the difference,'' Rafter said. "It could have easily been 6-4, 6-1, and the crowd would have booed me off the court.'' Instead, he broke serve at love in the fourth game to pull even at 2-2, and broke again in the last game of the second set when Lapentti missed four backhands on extended rallies.

On a roll: Pat Rafter reacts after his quarter-final victory over Ecuador's Nicolas Lapentti in the Italian Open yesterday. -- AP