Rob 'Gronk' Gronkowski announces retirement from Buccaneers, NFL on Instagram
Rob Gronkowski Announces Retirement From NFL For Second Time
Rob Gronkowski returns to Fox as NFL analyst after retirement
Rob Gronkowski Retired. Again. - The New York Times
Rob Gronkowski Announces 2nd Retirement From NFL
Former Patriots great Rob Gronkowski retires for a second time
Rob Gronkowski announces his NFL retirement, but his agent not convinced
Rob Gronkowski announces retirement from the NFL again - Newport Buzz
Gronkowski announces retirement from NFL