Thornton's contract option was considered a no-brainer since it called for the set-up man to make $3 million next season. He had a 2.67 ERA, while making a team-high 61 appearances. He even saved eight games, while posting a 5-4 record.
Thornton led all American League relievers with 81 strikeouts, as well as with a mark of 12.02 strikeouts per nine innings. He was eighth in strikeout-to-walk ratio (4.05) and eighth in holds (21). The last White Sox reliever to lead the AL in strikeouts was Keith Foulke in 1999.
Keeping the left-hander around makes sure the White Sox have one less bullpen vacancy for next season. Fellow set-up man J.J. Putz is a free agent, while closer Bobby Jenks, who could command a $9 million contract in salary arbitration, is not expected back.
After a solid season as the White Sox's backup catcher, Castro will earn $1.2 million next season. He drove in 21 runs in 37 games and his eight home runs were one less than A.J. Pierzynski had in 128 games
If the free agent Pierzynski doesn't return, Castro could be in line to become the starter behind the plate, although the White Sox are likely to pursue a veteran catcher in that scenario.
Torres, who came up from Triple-A Charlotte to pitch in five games with the White Sox (one start), was given his release so he could pursue an opportunity to pitch in a league in Asia.
Doug Padilla covers the White Sox for ESPNChicago.com.