Rob Gronkowski's dad isn't concerned about his son's head or health heading into the Super Bowl, telling TMZ Sports ... Gronk's fine, focused and ready to go!!!
He also put on a one-man dance show with wild friends chanting his name -- standard Gronk family swagger.
We got Gordon Gronkowski -- aka "Big G" -- heading into the Leather and Laces Party in Minnesota Friday night more than ready to have a good time ... and he doesn't even hint there's any reason to think his son's not going to have a great game
Patriots Nation's been uneasy all week about Gronk's status for Sunday -- since he just got medically cleared Thursday following a concussion in the AFC Championship -- but Big G says there's no reason to worry.