Richard Shotwell/Associated Press

Former New England Patriots tight end Rob Gronkowski said he wouldn't need much time to train for an NFL comeback should he decide to go that route.

"I could easily go out there right now and go," he said on the RapSheet and Friends podcast with Ian Rapoport of NFL Network. He added he would need a month—"if that"—of training.

Gronkowski also said he gets asked whether he will return "everywhere I go" and weighs 245 pounds, which is 15-20 pounds less than his playing weight.

Gronkowski, 30, walked away from the NFL in March with a Hall of Fame resume. The three-time Super Bowl champion, five-time Pro Bowler and four-time All-Pro selection was one of the best tight ends in league history.

He tallied 47 catches for 682 yards and three touchdowns last season, all of which were low by his standards. The Arizona product finished with 69 catches for 1,084 yards and eight touchdowns the previous year.

Gronkowski delivered in crunch time with a combined 12 catches for 166 yards in the AFC Championship Game win over the Kansas City Chiefs and Super Bowl win over the Los Angeles Rams.

Gronkowski appeared to have plenty left in his tank, but he stressed to Rapoport that the only way he will unretire is if his passion for the game returns.

"You always want to go with what you're truly feeling, even if it doesn't make sense to someone else. If it makes sense to you, then it makes sense to do that. If I get the gut feeling, that's what I would need. My soul would have to be on fire, and I wouldn't just listen to it for one day. It would have to be a consistent basis, too."