From the summer 1962 copy of the International Bank Notes (via World Bank Archives pages, PDF), we hear the story of World Bank President Eugene Black (from 1949-1963) arranging World Bank staff to take in Washington Senators baseball. According to the article, this annual event began in 1950 and continued through at least 1962. Early “baseball diplomacy”?

Presuming the dates are correct, this would have been RFK stadium. Looks right to me.