Cam Rayner is already turning plenty of heads at Brisbane Lions training, with teammate Sam Mayes labelling the talented youngster "an absolute star".

The No.1 pick in last year's NAB AFL Draft signed a new two-year contract extension during the week on top of the mandatory two years he received after being selected by the Lions.

The 18-year-old is now signed up until the end of the 2021 season, an important achievement for the Lions as they look to continually boost their player-retention rates.

"He's been training the house down. He's an absolute star. I can't wait to see what he can do," Mayes told RSN Breakfast Club.

"It's a credit to him. He's got a bit of security there now so he can just let his footy do the talking and not be worried by all that sort of (contract) stuff."

Mayes said Rayner's long-term commitment to the Club was an endorsement of the turnaround in culture at the Lions in the past few seasons.

"It's a positive for the playing group and the Club as to how we're tracking as well, because we've obviously made it comfortable for him to fit in," Mayes said.

Rayner drew comparisons with Richmond superstar Dustin Martin and Melbourne young gun Christian Petracca during his Draft year.

The Lions youngster is powerful in the way he uses his body in one-on-one contests and he can also play up forward or through the midfield.

Rayner averaged 18.5 disposals for Vic Metro at last year's NAB AFL Under-18 National Championships, of which 11.5 were contested.