After a broken 2007, Ozzie Guillen already has a guarantee for the White Sox in 2008. ''One thing I can guarantee -- of the five guys we have in the rotation, Jose Contreras will be the one who works the hardest this offseason,'' he said Saturday. ''With all due respect to Javier Vazquez, because he's a workaholic, and John Danks is a workaholic, I think Jose is the one who will work the most because he wants to come back and nail it. ''I made a prediction in spring training that Vazquez would be the most consistent guy we have, and he [has been]. I think right now, Jose will show up in the best shape and condition [in the spring] because he doesn't want to go through this summer again.''