The Baywatch is set to begin at Citi Field.

Free-agent slugger Jason Bay and the New York Mets have reached a preliminary agreement, a person familiar with the negotiations told the Associated Press yesterday.

The person spoke on condition of anonymity because Bay must pass a physical for the contract to be complete.

The three-time All-Star is expected to sign a 4-year contract for about $65 million. The 31-year-old outfielder hit 36 home runs with 119 RBI last season for Boston.

Bay is a career .280 hitter and has averaged 30 homers and 99 RBI in his last six seasons. Bay fills a huge hole in leftfield for the Mets, who skidded to a 70-92 mark during an injury-plagued year.

Bay produced in his 1 1/2 seasons with the Red Sox, but the sides couldn't agree on a new deal. That enabled the Mets to land a top free agent - a bat they needed for their decimated lineup, and the kind of splashy move their fans demanded general manager Omar Minaya make.

Bay and leftfielder Matt Holliday were the biggest hitters on the market. Holliday, who split last season in Oakland and St. Louis, is seeking an even richer deal than Bay.

Noteworthy

As expected, San Francisco signed versatile veteran Mark DeRosa to a 2-year, $12 million contract. DeRosa, 34, underwent left-wrist surgery after the season, when he batted .250 with a career-best 23 homers to go along with 78 RBI for Cleveland and St. Louis. The Phillies had some interest in the former Penn quarterback before they signed Placido Polanco to play third.