• Rob Gronkowski is retiring from the NFL.
  • Gronkowski is 29 and has played all nine seasons of his career with the New England Patriots.
  • Gronkowski will go down as one of the most talented tight ends of all-time, but injuries hampered his career.

New England Patriots tight end Rob Gronkowski is retiring from the NFL.

Gronkowski is 29 and has played nine seasons in the NFL, all with the Patriots. He was drafted in the second round by the Patriots with the 42nd pick overall.

Gronkowski announced his retirement via Instagram on Sunday.

"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," Gronkowski wrote.

"My life experiences over the last 9 years have been amazing both on and off the field. The people I have meet [sic], 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."

Gronkowski reportedly mulled retirement last offseason, but ultimately decided to return to the Patriots for the 2018 season. Gronkowski was mum on retirement at the end of the 2018 season, and his agent later told reporters that Gronkowski would make up his mind during the offseason.

Read more: Gronk brushes off question about his future, but his answer could be a clue that he has already decided to retire

Despite a relatively short career, Gronkowski will go down as one of the most skilled tight ends and offensive players in NFL history. He finishes his career with 521 total catches (130th all-time), 7,861 receiving yards (104th all-time), and 79 touchdowns (28th).

Gronkowski was named to five Pro Bowl teams, four All-Pro teams, and won three Super Bowls with the Patriots.

Of course, a big part of Gronkowski's career has been his injuries. He played all 16 games just twice in his career (2011 and 2012) and missed significant time in 2013 and 2016, playing just seven and eight games, respectively.

In 2017, Gronkowski turned to Tom Brady's TB12 lifestyle and was working with Brady's business partner and trainer Alex Guerrero, Gronkowski even boasted about being more "pliable" going into the 2018 season.

Despite that proclamation, Gronkowski struggled in 2018, playing 13 games and catching 47 passes (his lowest for any season he played 10 or more games since his rookie year), 682 yards, and 4 touchdowns. Many noted that Gronkowski looked less explosive on the field in 2018.

According to Spotrac, Gronkowski earned nearly $54 million over the course of his career. He told Business Insider in 2018 that he has only spent his endorsement money, saving his career earnings.

Read more: Rob Gronkowski has saved all of his $54 million in NFL earnings and has simple advice for young players entering the league

Gronkowski has become more involved in pop culture over the course of his career and has been said to be eyeing working in Hollywood when he's done with football.

"Now its [sic] 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," Gronkowski's retirement message said.