Piazza’s Signing Sets a Record : Baseball: Dodger catcher’s three-year, $4.2-million contract is the most for a second-year player.

The Dodgers broke policy Thursday, signing catcher Mike Piazza to a three-year, $4.2-million contract, the largest guaranteed contract in baseball for a second-year player.

It is the first multiyear contract offered by the club to a second-year player and will pay Piazza $600,000 in 1994, $900,000 in 1995 and $2.7 million in 1996, when he would have been eligible for arbitration.

“It’s good for the Dodgers and good for Mike for a number of reasons: One, because we have Mike under contract for three seasons and won’t be discussing contracts every year,” said Fred Claire, Dodger executive vice president. “And from an economic factor, we bought out a year of arbitration. If Mike continues to put up the type of numbers that he did, and I have no reason to believe he won’t, then when he enters the arbitration year, the Dodgers will have a pretty attractive contract.”

Piazza and his agents, Dennis Gilbert and Dan Lozano, have been negotiating with the Dodgers since late January, when the Dodgers initially offered Piazza a one-year, $500,000 deal, using as a comparable contract the $435,000 they paid Eric Karros after he won the 1992 rookie-of-the-year award.

That offer disappointed Piazza, who believed that his National League rookie-of-the-year numbers should be rewarded with a one-year deal worth at least $1 million. Piazza hit .318 with 35 home runs and 112 runs batted in in 149 games. Karros hit .257 in 149 games with 20 homers and 88 RBIs.

“(Negotiations) really weren’t going too well and it happened rather quickly, and I’m glad it did,” Piazza said from Boca Raton, Fla., where he is escaping the cold of his home in Philadelphia. “It’s a nice honor to be awarded the first multiyear contract and, like I said, I’m glad the club made that exception and recognized that beside any numbers, I also put my heart and soul on the field for the Dodgers and will continue to do so. I can relax now.”

All along, Gilbert kept comparing Piazza to Chicago White Sox first baseman Frank Thomas, who hit .318 in 158 games with 32 homers and 109 RBI in his first full season of 1991 and was given a three-year contract guaranteed for $4 million.

“Obviously we wanted a multiyear deal for reasons like security, and the highest deal was Thomas at $4 million for three years,” Gilbert said. “But the Dodgers told us from inception that they weren’t doing a multiyear deal, they had never done one, and then they made us a one-year offer. And that’s where they were.”

Piazza earned $126,000 last season, and the Dodgers had the option of renewing his salary, raising him or even cutting him 20%. All Piazza could do was not report to spring training when pitchers and catchers report next Thursday, an option he was considering. But Claire said the club’s change in philosophy is indicative of the direction the organization is heading.

“It’s a part of a transition of the Dodgers that is pretty evident,” Claire said. “When you look at Piazza, Delino DeShields, Eric Karros, Pedro Astacio and the young outfielders we have, we are building for the future while trying to be competitive for the present. There is a change, as there always is, that is taking place.”

The most the club had ever paid a second-year player previously was $485,000, to Ramon Martinez after he won 20 games in 1990, after one-plus years of service.