Ok, my Japanese mom translated it. Here it is:
The writing says this photo was taken on Sept. 9th, 1920 at Keio University grounds. The person in the photo is an American catcher named South (C. E. or L. E. ?). He is shown practicing after the game at Keio. He was a member of the All-Hawaii baseball team that was visiting Japan at the time.
Check out this website, same link as Ty gave previously:
http://faroutliers.wordpress.com/200...waii-1920s40s/
UPDATE:
The Japanese character for catcher and pitcher are somewhat similar. The writing on the card is not too clear. It looks more like catcher than pitcher, but looking at the photo it seems like he is a pitcher.