Pretty hard to say for sure, but my bet is it is the catcher, Josh Gibson. My reason being 3 observations. 1. Gibson had a habit of rolling up his sleeves as the batter has done and as can be seen in the team picture. Photos I've seen of him around this time with the Grays and Crawfords show his sleeves rolled up often. Not like he was the only ballplayer who did this, but it narrows it down. 2. The bottoms of his pants hang low over the stirrups, also something I noticed on a few Gibson photos. 3. The build of the batter is similar to Gibson in 1937.
Regardless of who it is, it's a nice one and the only one action shot I have seen from this particular team. Where did you find it? As a side not, I did a card of Satchel Paige who pitched for this team and talk a bit about the background of how these negro league players wound up in the Dominican Republic in 1937. If anyone is interested:
http://www.infinitecardset.blogspot....hel-paige.html