According to
Robert Mitchum, during the filming of the final fight scene between he and
Gregory Peck, Peck once accidentally punched him for real. Mitchum, knowing that Peck didn't mean to and ever the professional, refused to break character and continued filming the scene. However, upon entering his trailer, Mitchum said he "literally collapsed" due to the impact of the punch and said that he felt it for days after wards. According to Mitchum: "I don't feel sorry for anyone dumb enough who picks a fight with him (Peck)."
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