Patriots Place Rob Gronkowski on Reserve/Retire List 2 Days After Announcement

New England Patriots tight end Rob Gronkowski announced his retirement at 29 years old after nine seasons in the NFL on Sunday, and the Patriots made it official Tuesday. 

Per NFL Network's Ian Rapoport, the Patriots have officially placed Gronkowski on the reserve/retired list, which exempts Gronkowski from New England's salary cap and roster. 

Gronkowski exits the NFL owning 16 records, including most career postseason receiving yards by a tight end (1,163) and most touchdowns by a tight end in a season (18 total in 2011): 

His domination culminates in 521 receptions for 7,861 yards and 79 touchdowns across 115 games. Gronkowski played the game in a physical way and suffered countless injuries, which may be to blame for why arguably the best tight end in NFL history is walking before he turns 30.

The 6'6" University of Arizona product was selected in the second round (No. 42 overall) of the 2010 draft and spent his entire career in New England, winning three Super Bowls.

Following Gronk's retirement announcement on Instagram, several Patriots, including Tom Brady and Julian Edelman, expressed their love for the four-time All-Pro. 

"What an honor and privilege to play with you these past nine years @gronk!" Brady, in part, wrote in his Instagram tribute. "You accomplished so much and our team was almost unbeatable when you were on the field!" 

The admiration goes both ways. Gronkowski's agent, Drew Rosenhaus, said on ESPN's Get Up on Monday morning that his client wouldn't rule out a return:

The five-time Pro Bowler's retirement isn't a surprise. Gronkowski thought about calling it quits prior to last season. After the Patriots lost to the Philadelphia Eagles in Super Bowl LII, he told reporters: "I'm definitely going to look at my future, for sure. I'm going to sit down in the next couple of weeks and see where I'm at."

Gronkowski suited up for 2018 but not before the Patriots reportedly explored trading him to the Detroit Lions, which caused the tight end to take a harder look at retirement. "Brady's my quarterback, that's all," he told reporters after the team lost to Detroit in Week 3. "Wasn't going anywhere without Brady." 

Last season, Gronkowski appeared in 13 games (11 starts) and reeled in 47 catches for 682 yards and three touchdowns—his lowest totals since New England placed him on injured reserve with a back injury in 2016. 

While Brady is returning for his age-42 season, Gronkowski has had enough.