When you decide to personalize a sports jersey, you're walking on a very fine line. Want to turn your Rob Gronkowski jersey into one that just says, "Gronk," on the back of it? Sure, go for it. But when you decide to switch the jersey number to double zeroes and then write "Boobs" on top of that, then don't be surprised if you start running into problems.

So, in honor of all those misguided souls who still think that 69 jokes are funny enough to wear around, we made a gallery of The Worst Personalized Jerseys in Sports History. Let this serve as a word of warning to any of you out there who want to do a little something different with their custom jersey. And if not for yourself, please, just do that for us. 

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