Open with a straight sets win over Germany's Dirk Dier in yesterday's quarter finals.

On paper, the 22-year-old Australian Open semi-finalist has progressed smoothly to the last four, failing to drop a set in his three matches so far, but he has yet to reach top form -- and if and when he does that may be bad news for the three other men with their eyes on the title.

The Ecuadorean, who faces fourth seed Guillermo Canas today, admits he has not been at his best, but puts his success down to an inner confidence that comes with winning a lot of matches this year.

After his 6-4 6-4 victory over Dier, a win sealed with breaks as the German served to save either set, he said: "The score may sound easy but when you get close like that, when you get a tight match, it's the player who has been winning more matches and is more confident who almost all the time is going to win.

"I've been playing a lot of matches this year and I think, at the end, that counts for a lot.'' Dier said: "He's number 44 in the world so he's a pretty good player. But I should have given him more pressure in the match but for some reason I couldn't.'' However he denied he had felt the pressure when serving to save each set.

"When I had the chance I went for the shots. But if they go out by about five centimetres, what can I do?'' It was the third time the pair had met, with Dier beating Lapentti in their previous match at Coral Beach in 1996, but losing to him in July last year.

"He has improved a lot, but I mean I'm not so far away from that myself,'' added Dier. "I should think about that more in the match so I play from the very start, not just react.

"When I got the service break in the second set, it was the only good game for me in the match as far as I'm concerned.'' Indeed Dier was slow to start especially on Lapentti's serve which he lost to love. But when Dier did finally find his length he forced the first break point of the match, which Lapentti repelled.

Lapentti himself saw his first opportunity in a tight first set in the ninth game as a Dier double fault and backhand slice into the net gave him two break points for a 5-3 lead. But Lapentti, having opened up the court with Dier stranded on the forehand side, pushed his own forehand wide.

The South American won another break point when Dier double faulted again, but the German managed to hang on.

But he finally got the break he wanted as Dier served at 4-5, Lapentti beginning to make use of a clever sliced drop shot from the back of the court, mainly on his backhand but even more skilfully on his forehand side.

Dier briefly threatened by taking the first game on Lapentti's serve to love at the beginning of the second but Lapentti broke back to make it 2-2 and the match went with serve until Dier got to 4-5 again. At deuce, Dier blasted a forehand close to Lapentti on the baseline which was too much for the Ecuadorean to return.

But then he netted under little pressure and a great lob by Lapentti took a fortunate bounce further away from Dier to set up his first match point. Dier gave it everything but Lapentti passed him gloriously on the forehand side to clinch the contest.

Lapentti agreed that his drop shot had been very beneficial in frustrating his opponent.

"I used to use it a lot a couple of years ago, but sometimes I was using it too much, but now, on clay, I think it is very important,'' he said.

"You can get some variation on the points and it's also an aggressive shot -- the drop is not always defensive -- and I won a lot of points with it.

"I think maybe when you use that shot against some of the really top players, they read it a bit earlier but, also, Dirk doesn't move that well.

"He hits the ball heavy, so it's tough to move him around, but he doesn't move that well when you get in control of the point so sometimes I saw him standing way back and that's why I used the shot a lot.'' In yesterday's other quarter-final, Chile's Nicolas Massu moved almost unnoticed into the last four with a victory over Brazilian-born German Tomas Behrend 6-3 6-3.

It will be a major surprise if the 203rd ranked player in the world can make it to Sunday's final, because he was the last man to confirm his place in the competition.

But he slipped past Ecuador's Luis Adrian Morejon and eighth seed, Ville Liukko of Finland, before beating Behrend.

OPEN RESULTS AND SCHEDULE YESTERDAY'S RESULTS Singles Quarter-finals Nicolas Massu, Chile, d Tomas Behrend, Germany, 6-3, 6-3 Nicolas Lapentti, Ecuador, d Dirk Dier, Germany, 6-4, 6-4 Hernan Gumy, Argentina, d Jared Palmer, US, 6-3, 4-6, 6-1 Doubles Doug Flach and Richey Reneberg, US, d David Roditi, Mexico, and Paul Rosner, South Africa, 6-4, 6-4 Pat Rafter and Paul Kilderry, Australia, d Andrew Painter, Australia, and Maurice Ruah, Venezuela, 6-4, 6-4 TODAY'S SCHEDULE Centre court, 1.00 p.m.

First semi-final Nicolas Lapentti, Ecuador, v Guillermo Canas, Argentina Exhibition match Patrick Rafter, Australia, v Richey Reneberg, US Second semi-final Hernan Gumy, Argentina v Nicolas Massu, Chile Not before 4.00 p.m.

Doubles semi-finals Alejandro Hernandez, Mexico, and Cristiano Testa, Brazil, v Richey Reneberg and Doug Flach, US Mariano Hood and Lucas Arnold, Argentina, v Patrick Rafter and Paul Kilderry, Australia.