After further photo comparisons, I'm inclined to think that the player on the left is pitcher Jim Morio, who was a Reds' spring roster invitee in 1966. The only photo I have for Morio is his obituary picture. He died on March 16, 2012. He appears to have the same dimple and chin structure as the player on the left. His smile is a better fit than was that of Larry Himes. His head structure seems more elongated than Himes', which would be a better fit. Since the obit photo depicts Morio at an older age, it would be a reasonable assumption that his face would have looked thinner during his playing days.
http://www.baseball-reference.com/re...d=morio-001jam