Greenberg was playing for the Chicago Cubs on July 9, 2005, when he was hit by the first pitch he saw as a major leaguer. He spent the rest of the season on the disabled list, suffering from vertigo. He played in the minor leagues in various organizations and independent baseball since then.
He is expected to be given another chance at bat Oct. 2 when the Marlins play the New York Mets in Miami.
"I'm extremely proud to extend this opportunity to Adam," said Marlins owner Jeffrey Loria. "He has earned this chance as his love and passion for the game never diminished, despite his career tragically being cut short. I look forward to seeing Adam step up to the plate and realizing his comeback dream next Tuesday night."
Greenberg said his will donate his one-day salary to charity.
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