One clue made this one easy, and also brought up one of the worst things Leo Durocher did as Cubs manager.
To allow you to play along here, I have to show you the full version of the photo above, which is in a vertical format:
We have two easily identifiable people in this photo: Ernie Banks at the right, and Leo Durocher, who is looking at his catcher, who’s clearly in some sort of distress.
Your next clue is the baseball 100th anniversary patch on Leo’s right sleeve. That was worn only in 1969.
So, the only way to figure out when this photo was taken was the visiting player also standing over the catcher. We only see a “3” on the back of his uniform. Thankfully, in those days many teams put players’ numbers on batting helmets. You can clearly see “23” on the back of the helmet, and that numbering style was used by the Dodgers in that era.
Claude Osteen, a mainstay of the Dodgers’ rotation from 1965-73, wore No. 23 for them in 1969.
Source:: Bleed Cubbie Blue