Continuity mistake: The sun changes considerably when Doc is leaving to walk into the corn and the previous and following shots. When it cuts to Shoeless Joe, the sun is at his back. Back to Doc leaving, the sun is setting.
Continuity mistake: The clock at Fenway jumps two minutes in very little time from 10:30 to 10:32 in the space of two short scenes.
Continuity mistake: During the first practice, the sun changes from late afternoon initially to midday and back to late afternoon throughout the sequence.
Factual error: The catcher appears with the other players when they come out of the corn. The catcher was never included in the scandal, nor was a catcher banned.
Answer: It was actually his own voice (Kevin Costner) that sent him on the journey. At the end of the movie there's even the part where Ray is recalling the voices he heard and turned to Shoeless Joe Jackson and says, "It was you". At which point Joe Jackson turns around and says, "No Ray. It was you".