Chilean clay court master Marcelo Rios earned $350,000 without lifting a racket here on Sunday as Spanish opponent Albert Costa retired with a wrist injury before the start of the final at the Italian Open. Rios remained the form player of 1998 as he picked up his fourth title of the year.

Costa, ranked 20th in the world, fell hard on his right wrist after hitting a forehand on the first point of the final game during his 6-3, 4-6, 6-3 semi-final win on Saturday over compatriot Alberto Berasategui.

The 22-year-old Spaniard, dusted himself off and carried on for the victory. But during the night Costa said that the injury took a turn for the worse.

"At 9:30 or 10 at night I was feeling pain, very bad pain," said Costa. "I was a afraid that if I did not improve a lot I could not play. The wrist it swelled up, in one hour, it was really bad. I don't know how it could have happened so fast."

Costa underwent treatment on Saturday afternoon and tried to practice shortly before the scheduled Sunday start of the Cente Court match. "I tried to hit the ball, but I had no power," said Costa. He will return to Barcelona for treatment of an injury which the tournament doctor said could require from four to 25 days to completely heal.

"There was no way I could play," said a Costa. "If this had been the French Open final, it would have been the same."

Rios said: "It's not the best way to win. But I've played really good all week. It was bad luck for Albert, but that the way it goes. We're tennis players and we can sometimes get injured."

Rios was this week competing in only his second event since missing a month with an elbow injury. That problem prevented him from playing a Tour match as the world number one after taking over the spot from Pete Sampras.

The uncompleted final was the first at the Foro Italico since 1991, when Emilio Sanchez won as Argentine Alberto Mancini retired.