Top seeds Marcelo Rios reached the semi-final of the Sicily International after beating David Sanchez in a tough three set battle.

Rios prevailed 7-5 4-6 7-6 and could face fellow Chilean Fernando Gonzalez in the final if both win their semi-finals.

Second seed Gonzalez advanced to the last four with a 6-2 7-5 win over Spaniard Alberto Martin.

Gonzalez's win means that he will move ahead of Rios in Monday's Entry System rankings to become Chile's top-ranked player for the first time.

He has not dropped a set this week and has won 12 of his last 15 matches on the ATP circuit, including appearances in the quarter-finals of the US Open and the semi-finals of the Cincinnati Masters.

In the semi-finals, Gonzalez will meet the Czech Republic's Bohdan Ulihrach, who held on to defeat Sargis Sargsian of Armenia 7-5 1-6 6-4.

"It was tough to play today because of the conditions. It was very windy, and the shadows and sun were on the court," said Gonzalez.

"That's why I changed my strategy. I'm known as a hard hitter but I had to use other resources to win the match."

Rios prevailed after a thrilling contest with sixth seed Sanchez, who held a match point at 7-6 in the third-set tiebreak.

But Rios stormed back to win the final three points to close out the match.

He will face third-seeded Argentine Jose Acasuso who continued his strong run on clay by defeating Peru's Luis Horna 7-5 6-0.

The teenager has won 18 of his last 20 matches on the surface.

Friday's Salem Open results

Quarter-finals

(3) Jose Acususo (Arg) beat Luis Horna (Peru) 7-5 6-0
Bohdran Ulihrach (Cze Rep) beat Sargis Sargsian (Arm) 7-5 1-6 6-4
(2) Fernando Gonzalez (Chile) beat (7) Alberto Martin (Spa) 6-2 7-5 (1) Marcelo Rios (Chi) beat (6) David Sanchez (Spa) 7-5 4-6 7-6