 On December 13, 2007, Carreon was named in the Mitchell Report to the Commissioner of Baseball of an Independent Investigation Into the Illegal Use of Steroids and Other Performance Enhancing Substances by Players in Major League Baseball.Carreon was a rarity, in that he threw left-handed but batted right-handed, as a non-pitcher.Mark Carreon spent the next two years playing pro ball in Japan for the Chiba Lotte Marines after the 1996 season.