[baseball tourist]

Originally Posted by prestigecollectibles

If the date on the back is accurate then it is from the 1959 Japan Series. The Nankai Hawks swept the Yomiuri Giants in four games.
October 27th and 29th were played at Korakuen Stadium in Tokyo. The 28th was rained out.
Both Sadaharu Oh and Shigeo Nagashima were in the lineup on the 27th. Nagashima played, but Oh didn't on the 29th.

Since the front says it was a regular season game I guess it's possible that the date stamp was placed there later.

Thanks Robert!