If there was any lingering question about whether Rob Gronkowski plans a last-minute return to the NFL in 2019, the chances appear to have dropped significantly.



Right along with his weight, apparently.



In the clearest sign yet — aside from Gronkowski repeatedly insisting he is retired — the former New England Patriots tight end popped up for the premiere of Showtime’s “100 percent: Julian Edelman” premiere looking like he’d slimmed down considerably from his 270-pound playing weight during the season. Gronkowski briefly appeared on the red carpet for the documentary’s debut at Foxborough’s Showcase Cinema de Lux — a movie theater located inside owner Robert Kraft’s Patriot Place retail complex. Wearing gray shorts and a white T-shirt, Gronkowski mugged for cameras for a moment, showing off a physique that looked significantly more trimmed down than his playing days.



So much so, it started a miniature wildfire on Twitter over the photos and video that emerged — including some snarky comments about where some of the muscular bulk went to so quickly.



“Must be on a different #TB12 program now,” tweeted former NFL team doctor David Chao, who has earned a sizable social media following for his ability to diagnose injuries almost instantaneously on the platform.

Must be on a different #TB12 program now.https://t.co/ykesHFGpOB — David J. Chao (@ProFootballDoc) June 30, 2019

Intended or not, that appears to be a little shot at Gronkowski being one of the prominent Patriots who were followers of Brady’s less-than-conventional TB12 health regimen. Gronkowski has also been known to be a client of Brady’s trainer Alex Guerrero, who has been a somewhat controversial figure around the franchise due to his medical and training influence over players.

Of course, muscle atrophy (or even simple weight loss) naturally happens to some NFL players that are Gronkowski's size, partly because some players have to work to keep their weight up to a level that makes them durable during the season. Often, players in the 270- to 300-plus pound range have to work to maintain their playing bulk. And when they leave, some of that weight or muscle mass can change quickly. What makes this particular weight loss so relevant for Gronkowski's future is that it's more difficult to quickly and conventionally add back a significant amount of good weight or muscle mass, particularly if you're a player who had to work to keep that weight on in the first place.

Gronkowski also isn’t the first NFL player experiencing some noticeable changes in his physique since leaving the game. Former Cleveland Browns left tackle Joe Thomas lost nearly 50 pounds in the first year after he left the league — turning his body into a chiseled frame that looks more like that of a linebacker who is moonlighting as a bodybuilder. Thomas said he achieved the results through a lot of hard work and some big dietary changes in his first year out of the league.

Time will tell where Gronkowski decides to go from here. But for now, at least two things are evident. First, as we expected, he’s clearly enjoying his retirement thus far — having popped up at multiple social affairs this offseason while reiterating that he intends to remain retired. And second, the latest photos from suggest Gronkowski is illustrating the physical changes that show he’s committed to the message: He’s not coming back anytime soon (if ever), folks.

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