Rob Gronkowski, 4-Time Super Bowl Champ, Retires from NFL a Second Time
Rob Gronkowski Retired. Again. - The New York Times
Rob Gronkowski retires for second time following decorated 11-year career with Patriots, Buccaneers
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Former Patriots great Rob Gronkowski retires for a second time
Rob Gronkowski Intends To Retire
Buccaneers tight end Rob Gronkowski retires for second time
Rob Gronkowski announced as featured speaker for Arizona Bowl luncheon
Rob Gronkowski announces retirement from the NFL