Ruth Turner, 92, tucked a fresh score book into her backpack and made her way from her apartment on the Upper East Side of Manhattan to the 4 train bound for Yankee Stadium in the Bronx.

She settled into her regular seat in Section 105 behind right field to watch the Yankees play the Mets last week.

Ms. Turner, who has been keeping score for 25 years, barely had to consult the scoreboard to jot the two teams’ lineups on her score sheet, along with batting averages, fielding positions and other information.

As the Yankees took their positions on the field, Ms. Turner settled into hers: marking the plays with her right hand and holding a Sony pocket radio to her ear with her left, for the game broadcast.