Here's Frank Duncan. When people think of the Kansas City Monarchs, they usually think of either Satchel Paige or Buck O'Neil. But the REAL Mr. Monarch was Frank Duncan. He had a 25 year career in the Negro Leagues as a player, with 21 of them on the Monarchs. But he also managed the team for most of the 1940s. SABR has a great biography of him, which you can read here:
https://sabr.org/bioproj/person/frank-duncan/
The card in the top left is the one in this set.