Performance-enhancing substances, which had made headlines in the sport for the past several years, became a factor in voting for the first time. Two MVP winners who later admitted to steroid use – José Canseco and Ken Caminiti – were both among the first-time candidates. More prominently, McGwire was appearing on the ballot for the first time; considered a highly likely first-ballot selection following his record-setting home run feats in the late 1990s, his candidacy was heavily debated more recently as observers of the sport considered both his admitted use of legal dietary supplements (particularly androstenedione, which he stopped using in 1998 and was banned in 2004), as well as suspicions in some quarters that he had also used steroids (which he ultimately admitted in 2010 to having used for much of his career, including 1998). The voters took these matters into consideration, individually determining how recent offensive totals should be regarded by the Hall, as the first players from the sport's offensive explosion in the late 1990s now began to appear on the ballot in significant numbers.