Good news Gronk, the star of such classics as "Dynamic Booty 5" and "Bubble Butt Bonanza" says you have a future in the skin biz ... and she's being totally serious.
TMZ Sports talked to Richelle Ryan -- star on over 200 adult movies -- who happens to be a hardcore football fan ... in addition to the other hardcore stuff she's into.
So, naturally, we asked which NFL player would make the best horizontal All-Pro -- and that's when she gave Rob G the XXX stamp of approval.
Don't rule it out Gronk, when the star of "Baby Got Boobs 8" gives you career advice you take it ...