The Chicago White Sox bought out Frank Thomas for $3.5 million on Friday, making the best slugger in team history eligible for free agency. The 37-year-old Thomas exercised a $10 million mutual option for next season on Monday, giving the team five days to decide whether to exercise its half. The White Sox could try to re-sign the two-time AL MVP for less money. ``There should be no question about the respect this organization has for Frank and all that he has helped us accomplish, including a World Series championship,'' general manager Ken Williams said in a statement. ``He is the greatest hitter in White Sox history. At the same time, it is my responsibility to make the best decisions I can on behalf of the organization. Our plan now is to continue to speak with Frank and his representatives over the coming months as more information is known about his health.''