Koch had lost closer's job in Chicago
The deal was announced shortly after the Marlins beat the White Sox 2-1 in 12 innings.
The Marlins acquired Koch and cash from the White Sox, who had recently replaced the right-hander with Shingo Takatsu -- Japan's all-time saves leader -- as the team's closer.
"I was sort of expecting it a little bit, but I didn't think (Florida)," Koch said. "Through the grapevine, I hear things. I never heard the Marlins, but it'll be good. I like the heat, I like the sun."
Koch, 29, never quite fit in with the White Sox after joining them last season. He appeared in 24 games this season with eight saves in 11 opportunities and a 1-1 record -- but had a 5.40 ERA. Koch allowed 24 hits and 15 runs in 23 innings.
"That will be the best scenario for him," White Sox manager Ozzie Guillen said. "It's a shame it didn't work out for him here because he was a class act."
The Marlins were in need of bullpen help in the middle innings to complement a solid starting rotation and closer Armando Benitez. Before trading for Koch, the Marlins' latest acquisition was 36-year-old Josias Manzanillo, who was called up from Triple-Albuquerque on Wednesday.
"He's a proven closer who knows how to handle games late," Marlins general manager Larry Beinfest said of Koch. "We'll put him right in that spot, in front of Benitez.
"Maybe a change of scenery will be good for him."
Koch is 28-23 with 163 career saves in six major league seasons with Toronto, Oakland and Chicago.
The 25-year-old Valdez was hitting .319 in 66 games at Albuquerque. Florida claimed him off waivers from Montreal in March 2002.
Copyright 2004 by The Associated Press
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