On Sunday, arguably the best tight end in NFL history called it a career.

After months of speculation, New England Patriots star Rob Gronkowski announced on Instagram that he would be hanging up his helmet at the age of 29.

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It all started at 20 years old on stage at the NFL draft when my dream came true, and now here I am about to turn 30 in a few months with a decision I feel is the biggest of my life so far. I will be retiring from the game of football today. I am so grateful for the opportunity that Mr. Kraft and Coach Belichick gave to me when drafting my silliness in 2010. My life experiences over the last 9 years have been amazing both on and off the field. The people I have meet, the relationships I have built, the championships I have been apart of, I just want to thank the whole New England Patriots organization for every opportunity I have been giving and learning the great values of life that I can apply to mine. Thank you to all of Pats Nation around the world for the incredible support since I have been apart of this 1st class organization. Thank you for everyone accepting who I am and the dedication I have put into my work to be the best player I could be. But now its time to move forward and move forward with a big smile knowing that the New England Patriots Organization, Pats Nation, and all my fans will be truly a big part of my heart for rest of my life. It was truly an incredible honor to play for such a great established organization and able to come in to continue and contribute to keep building success. To all my current and past teammates, thank you for making each team every year special to be apart of. I will truly miss you guys. Cheers to all who have been part of this journey, cheers to the past for the incredible memories, and a HUGE cheers to the uncertain of whats next.

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Gronkowski was an unstoppable force on the football field.

Over the course of nine seasons with the Patriots, Gronk caught 79 touchdown passes, the most during that time span. In 115 regular-season games, the Arizona product caught 521 passes for 7,861 yards. He also caught 81 passes for 1,163 yards and 12 touchdowns in the playoffs, all of which are records for a tight end. 

With Gronk stepping away, the mantle of best tight end in the NFL likely will fall to either Chiefs star Travis Kelce or George Kittle.

After a decent rookie season in 2017, Kittle cemented himself as an All-Pro tight end in 2018. The 25-year-old caught 88 passes for 1,377 yards and five touchdowns in last season while breaking Gronkowski and later Kelce's record for most receiving yards by a tight end in a season.

The Iowa product put together a historic season with star quarterback Jimmy Garoppolo missing all but three games with a torn ACL.

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Assuming Jimmy G makes a full recovery in time for the 2019 season, there's no reason to think Kittle won't put up astronomical numbers once again this season.

While Kelce and Eagles tight end Zach Ertz will continue to be in the conversation for best tight end along with Kittle, the 49ers star appears primed to take the mantle from Gronk and become the premier tight end in the NFL.