Thanks to his jersey, there's no excuse for not knowing this is 'J.D.' Martinez
The back of J.D. Martinez's jersey reads "J.D. Martinez". In a league where some teams don't even have last names on their uniforms, sporting one's first and last name is quite the rarity.
But Martinez hasn't always had the "J.D." on his jersey ...
So what gives?
There's a likely and simple reason, of course, for J.D. Martinez's jersey moniker: Victor Martinez. The senior Martinez joined the Tigers three years before J.D., thus securing dibs on the Martinez jersey (as you can see in the top photograph). And if he was going to put "J. Martinez" on the back of his, might as well splurge for that second letter, right?
If you're wondering, the J.D. stands for Julio Daniel. That would probably be stretching it on a jersey, but if he keeps hitting home runs this postseason (he has two in the ALDS against the Orioles), he might just earn it.