Rob Gronkowski Says He Could Return To Patriots In 2020, 'I Still Stay Fit'

Rob Gronkowski ain't coming back to the New England Patriots this season ... but he says he might just rejoin Tom Brady and Bill Belichick in 2020!!

"I still stay fit, still watch the game whenever I can, still enjoy it," Gronk said. "I'm feeling good, but you know, one year off could possibly be the case."

Gronk officially ruled out a return to Foxborough this season with the announcement that he'll be hosting a festival in Miami during Super Bowl weekend instead of training for it.

But, when the 30-year-old superstar spoke with ESPN about the party plans Tuesday ... he left the door wide open for a Patriots return either next year or even in 2021.

"It's always an option in the back of my head," Gronkowski said. "It's not like I'm not staying in shape and not doing anything. I'm never stressed over it."

It's a bit of good news, bad news for the Patriots ... 'cause their offense has REALLY struggled over the past couple weeks and they definitely could use Gronk ASAP.

In fact, Gronk even joked about their issues, saying, "Man, they're missing some guy who is 6'6", 260 [pounds]. They're missing that guy, for sure."

But, if the future Hall of Fame tight end does return next year ... it could help the team keep Brady -- who's a free agent after this season -- for one more year.