New York ? Frank Thomas decided to remain with the Chicago White Sox, and it looks as if Sammy Sosa will stay with the Cubs.

Thomas decided Thursday to exercise his $6 million option rather than risk becoming a free agent.

“He felt we had some unfinished business to take care of,” White Sox general manager Kenny Williams said.

Sosa has until Saturday to decide whether he wants to opt out of his contract, which guarantees him $33 million over the next two years.

Given that many teams say they plan to cut spending or maintain payrolls at their current levels, it appears highly unlikely Sosa will decide to test the market.

“The market is different now than it was in 1998 and 1997,” Adam Katz, one of Sosa’s agents, said Thursday. “Sammy is a bright, pragmatic guy. He also has indicated to everyone that he’d like to stay in Chicago and retire with the Cubs. That being said, we’re going to let people know probably tomorrow.”

Thomas re-signed with the White Sox after becoming a free agent a year ago, getting a contract that guaranteed him $22.5 million. Thomas has options for $8 million in 2005 and $10 million in 2006, a year that has a $3.5 million club buyout attached to it. If he declines his options, the White Sox could hold onto him for $11 million in 2005 and $12 million in 2006. A two-time AL MVP, the 35-year-old first baseman and designated hitter hit .267 with 42 homers — one shy of his career high — and 105 RBIs.

“After weighing our options, we felt the best decision for Frank was to return to the White Sox,” said Thomas’ agent, Arn Tellem. “I know Frank would like nothing better than to help the White Sox win a World Series title.”

The Cubs declined a $2.2 million option on Mark Guthrie, deciding to give the left-hander a $300,000 buyout. Guthrie then filed for free agency.

Tampa Bay and Travis Lee declined a $2.5 million mutual option, which means the first baseman will get a $500,000 buyout. Lee, who hit .275 with 19 homers and 70 RBIs last season, became eligible to file for free agency.

“We understand why Travis would want to explore free agency, but there still exists the possibility for him to play for us next year,” Devil Rays general manager Chuck LaMar said.

Los Angeles right-hander Paul Quantrill filed for free agency after exercising his right to void the final year of his contract, which was worth $3.1 million.

A total of 26 players filed for free agency Thursday, raising the total to 175 among the 225 potentially eligible. Among those who filed were White Sox second baseman Roberto Alomar, Atlanta third baseman Vinny Castilla and San Francisco outfielder Jose Cruz Jr.