Rob Gronkowski announced his retirement in March and has since opened up about why, including that he needed to prioritize his health. The former New England Patriots tight end will appear on HBO's "The Shop" in its return on Tuesday, and a preview shows Gronk discussing why he decided to leave the football world. 

He explains when the first sign that he might need to hang up the cleats came:"It was about like two years ago, it was like a game changer in my life where I was trying to go out to the practices during the summer and I was getting smoked by every rookie."

Gronk goes on to say that he had to look ahead past football, "In order to do something bigger in life ... I felt like I had to get away from the game and focus on my health."

The 30-year-old suffered multiple injuries to his forearm, back and knee in his career and while he often made an unmatched impact on the field, there were many seasons when he was not able to play every game due to health reasons. He notoriously had to wear a large brace on his arm, making the 6-foot-6, 268-pound athlete look more like a robot than a human being. 

The three-time Super Bowl champion went on to discuss his bad off the field habits, including what he ate and drank and how much he was partying. The group he talks to on "The Shop" agrees that "you can't be a rockstar and a football player," the way Gronk describes he was trying to be. 

The larger-than-life personality has not yet closed the door on a comeback and said in his CBD partnership announcement, "When that time comes down in the future, if I have the desire to play football again, if I feel passionate about football again, if I feel like I need to be out there on the field, I will go back to football."