Gronk's agent wouldn't be shocked if he returns during 2019

At least one person close to Rob Gronkowski isn't fully closing the door on his playing career, even after the all-time great tight end announced in an Instagram post on Sunday that he's retiring from the NFL and will "move forward with a big smile."

Gronkowski's agent, Drew Rosenhaus, said he wouldn't be surprised if the tight end returns to the New England Patriots at some point in 2019.

"If the team was struggling or they needed him at some point next year, and let’s just say hypothetically Tom Brady gave him a call and said 'Rob, I need you.' I wouldn’t be shocked if he came back to play a few games," Rosenhaus told the hosts of "Get Up!" on ESPN, according to Adam Schefter.

If Gronkowski does decide to unhang up his cleats, he wouldn't be the first player to do it. Heck, he wouldn't even be the first future Hall of Fame tight end to do so this year. Jason Witten, who retired in May 2018 before spending last season as a Monday Night Football commentator, declared his intention to rejoin the Dallas Cowboys in late February.

Time away from the locker room apparently reignited Witten's passion, so could it do the same for Gronkowski?

Perhaps the better question is whether time to heal might change Gronkowski's mind. Nine seasons of big catches, tough blocks, and significant injuries seemed to weigh heavily on the 29-year-old in 2018. He also made just three touchdown catches in the regular season, a career-low number.

Still, Gronkowski was at his best when the stakes were highest in the postseason. His final catch, made late in Super Bowl LIII, helped set up the Patriots' winning score.

As Gronkowski told Rosenhaus, according to King, he's "going out on top." For now, at least.