The off-contract Giants midfielder doesn't boast the Brownlow Medal of Nat Fyfe or the tattoos of Dustin Martin. He's tucked away in Sydney where AFL takes a back seat to rugby league in the media, and that suits him just fine.

His silky skills and ball-winning ability are underpinned by a maturity and quiet calmness rarely seen in a 22-year-old.

On the field Kelly is a ball magnet. He's in career-best form and has played a huge role in the Giants' strong start to the season.

But off it he keeps his head down: he doesn't chase headlines and he behaves himself as he always has done, so as not to jeopardise what is quickly growing into a super AFL career.

The worth of that career has grown exponentially this year. At the moment he has a two-year offer on the table to re-sign with the Giants, who drafted him at the end of 2013 with pick No.2.

He is also weighing up a reported nine-year, $9 million offer to join North Melbourne. And St Kilda are also believed to be interested in his services, after failing to lure Fyfe from Fremantle.

North and St Kilda both have cash reserves to make a serious play for Kelly, the former also reportedly interested in Martin.

Kelly was asked about his future during the week and handled the inquisition with aplomb.

He will make the decision when the time is right, he said. He loves playing for the Giants but it is a big decision and he has no interest in rushing the process.

It is a maturity Kelly has always had, says AFL national talent manager Kevin Sheehan.

"Absolutely low maintenance is what we call them; never an issue with him, there was never going to be an issue," Sheehan said.

"He was so respectful in every way as a young man. Coming through the Vic Metro program, Sandringham, Brighton, all the places he'd been he had a fantastic reputation for being a young leader.

"He was always destined to be a very good player at the highest level.

"With his father, Phil, being a top player he was able to get good mentoring along the way as well. The head completely on the shoulders, no distractions there, and was able to manage the challenges of a young fella trying to make it into the professional AFL life."

As for Kelly's on-field brilliance, Sheehan said that would always come once he built his body. He weighed 73 kilograms during draft year, and Kelly has put on almost 10 kilograms since joining GWS.

"The frame was always going to take a little bit of time to fill out, that was the only thing you were waiting on," Sheehan said.

"As a young kid, he was just so highly regarded. He was an exciting player to watch at under-age level, you don't say that of all the boys.

"His courage in the air for a kid so light would be a thing you take away one day. Then the way he ran, he'd run quickly and run all day. His use of the ball was always pretty special as well. He had everything but the frame.

"His body's matured, he's really just the complete package in terms of what you're after: unflappable player in the game, great leader and role model off the ground as well and a consistent performer at a very high level week in week out."