Frank Viola and the New York Mets failed to agree on contract extension yesterday and the left-hander says he's headed for free agency after the season.

Viola, 20-12 in 1990, is looking for a deal similar to the one the Mets gave Dwight Gooden on Monday. Gooden signed a three-year deal for $15.45 million and he can make as much as $16.2 million with incentives.

The Mets have offered Viola $13 million for three years, up from their last offer of $12.5 million.

"Frank enjoys playing for the Mets, but not enough to forfeit millions of dollars," said Viola's agent, Craig Fenech. "Why should he sign for a million dollars less than he can get as a free agent?"

The Mets acquired the former St. John's star and Cy Young Award winner in July 1989 from the Minnesota Twins in a multi-player deal. He said at the time it was always one of his dreams to play in New York.

"We're talking about two outstanding pitchers [Gooden and Viola]," Mets vice president Al Harazin said yesterday. "With Doc, we went beyond what we planned."

Fenech said his client does not wish to negotiate during the season.

* GIANTS: X-rays taken of Will Clark's injured ankle were negative, but the first baseman was held out of an exhibition game against the Oakland Athletics as a precautionary measure.

Clark sprained his right ankle during a workout Friday night before the opening game of a three-game series against the A's. Clark had two singles and a double in three at-bats before being removed in the sixth inning.