Remembering Mets History (1998) The Mets Acquire Mike Piazza & His Met Legacy Begins
It was a blockbuster deal with some big names of the day involved. Piazza was set to be a free agent at the end of the season. As one of the biggest stars in the game he was looking for $105 million over seven years & the Dodgers were offering $76 million over six years. The fans & the media thought his demands were too high. Piazza felt legendary Dodger broadcaster Vin Scully had a lot to do with the criticism.
The deal was made with the Marlins & is considered one of the worst trades in Dodger history.
The Florida Marlins had won the World Series the previous year & wanted to cut salary. They would shed over $22 million on this trade alone. In 1998, the Marlins had a big-league fire sale, dumping all their big salaried players. In acquiring Mike Piazza, it would give them a big chip to trade for more top young prospects. 
After the 1997 Marlin Championship, The Mets traded for one of their top pitchers in Al Leiter, in exchange for pitching prospect A.J. Burnett.
At this point in time, both teams GMs were on good terms, making it easier for negotiations leading up to the Piazza deal.
At that time, the Mets main catcher was Todd Hundley, but he was out with a long-term injury. Alberto Castillo was filling the role, but he wasn't the answer.
The Mets were now under manager Bobby Valentine; they were changing direction & moving forward. The team was getting better & adding Piazza would give them the catcher they needed, as well one of the best hitters in the league.
On May 22, 1998, the news broke in New York to the delight of Mets fans; Mike Piazza was coming to Shea Stadium in exchange for Preston Wilson, Ed Yarnell, & Geof Getz.
The rest is Mets history. Piazza went on to become one of the greatest players in franchise history getting into the Baseball Hall of Fame wearing a Mets cap.
After a slow start upon his arrival, he became a New York icon. In just playing part of that season, he helped bring them within one game of the playoffs.
He In 2004 Piazza would set the MLB record for most HRs all time by a catcher. He would get inducted to the teams Hall of Fame & have his uniform #31 retired by the team. As mentioned, he went to Cooperstown joining Tom Seaver as Mets immortals in the Baseball Hall of Fame.
The Other Players: Preston Wilson did well in Florida, he hit 23 HRs or more in all four seasons he played there. He had 100 plus RBI season as well but never hit above .280.
In 2003, when the Marlins won their second World Series, Wilson was already gone. Ed Yarnell was a top AAA pitcher at the time of the trade but soon faded away. Geof Goetz never made it to the big leagues.