Once again, there’s a clue to this photo via the Getty Images supplied caption, but not much of a clue:
Outfielder Roberto Clemente #21 of Pittsburgh Pirates racing to first base against the Chicago Cubs during a MLB baseball game circa early 1970’s at Wrigley Field in Chicago, Illinois. Clemente played for the Pirates from 1955-72.
Circa early 1970s... well, that narrows it down, at least.
The first clue is the Pirates uniform. The Bucs were the first MLB team to switch from wool button-downs to polyester pullovers with the no-belt look.