Rob Gronkowski closes the door on possible NFL comeback, says he's 'happily retired'
Rob Gronkowski returns: Ranking the 10 best NFL comebacks out of retirement in history
Rob Gronkowski Announces Retirement From The NFL – Hollywood Life
Rob Gronkowski retires (again) from NFL, revisited: Why former Buccaneers, Patriots tight end called it a career
This story about Rob Gronkowski faking his offseason workouts might be the greatest Gronk Tale ever told, This is the Loop
Goodbye to Rob Gronkowski, Who Made It Look So Easy
Rob Gronkowski to 'take some time' to mull NFL future, reveals 2 things he still wants to accomplish
Rob Gronkowski retiring from NFL for second time - CBS Boston
Gronk's legacy: How does he stack up among the best to ever play tight end? - The Boston Globe
Rob Gronkowski retires, won't join Tom Brady for 3rd season
Tom Brady Won't Try To Talk Rob Gronkowski Out Of Retirement
Rob Gronkowski and 5 Other NFL Players Whose Careers Could Be Over, News, Scores, Highlights, Stats, and Rumors