The fan who caught Shohei Ohtani's historic 176th home run is about to be a whole lot richer ... TMZ Sports has learned the man's putting the ball up for auction -- and it's expected to net him a small fortune!!
The guys over at Heritage Auctions tell us ... Jason Patino -- who snagged the record-setting baseball after Ohtani blasted it toward him in an April 21 victory over the Mets -- is selling the memento on their block, and they're figuring it'll eventually go for around $200,000.