It's a true story ... the NFL superstar tells TMZ Sports he's been a fan of cryptocurrency for years and believes it's eventually going to be the standard way people pay for things like groceries and clothes.
Of course, the price per coin was around $2.00 in 2011 ... and grew to around $1,000 by the end of 2013. It didn't really pop again until 2017 -- when it soared to more than $19,000 PER COIN!!
So, how much money would Sherman have made?? A lot.
Don't feel too bad ... Sherman says he did make some profit -- just not the gazillions that people like the Winklevoss twins hauled in. And the experience hasn't ruined cryptocurrency for Sherman ... 'cause he's now a spokesperson for a new trading platform called Cobinhood.
Plus, he signed a $56 million contract extension in 2014 ... so he ain't losing sleep over it.