Mark McGwire is one of the greatest home run hitters of his era. During his first season in 1987, "Big Mac" led the league in HR with 49 and was named Rookie of the Year. Splitting time between Oakland and St. Louis throughout his 16-year career, McGwire and former Chicago Cubs rival, Sammy Sosa, captivated the nation during their HR chase in 1998. That season, McGwire hit an unprecedented 70 HR, blowing away the previous record of 61 held by Roger Maris. McGwire finished his career with 583 HR, was named to the All-Star team 12 times, and won a World Series Title in Oakland in 1989. Mark McGwire has hand signed this Oakland A's Full Size Rep Helmet. Bold Black Full Pristine Signature. Schwartz Sports Hologram. Image of actual item in stock - as shown