context: McCallister was Tris Speaker's primary assistant during his years as player-manager (1919–1926).
source: McCallister became manager after Speaker's sudden resignation in late 1926.
reference_original: McCallister wurde nach Speakers plötzlichem Rücktritt Ende 1926 Manager.
reference_flipped: McCallister wurde nach Speakers plötzlichem Rücktritt Ende 1926 Managerin.