Former Brisbane captain Jonathan Brown believes GWS Giant Tom Scully is the best two-way runner the competition has ever seen.

The 25-year-old is blessed with lightning quick speed and has the stamina to match, and Brown believes those two attributes contribute to making Scully a once in a lifetime midfielder.

“I played with a couple of great two-way runners,” Brown told Fox Footy’s On The Couch on Monday night.

“The great Shaun Hart and especially Nigel Lappin, who was unbelievable. I’m prepared to put in on record: I think Tom Scully is the best two-way runner I’ve seen.

“His running ability — both ways — is second to none. I know we’ve had some great endurance midfielders who’ve chased the ball really hard, but Scully is unbelievable.”

Scully has started the season strongly for the Giants, averaging 25 possessions a game and using the ball at 85% efficiency, which sees him rated by Champion Data in the elite category for efficiency by foot.

The former Demons midfielder dominated in GWS' 31-point win over Port Adelaide on the weekend, collecting 32 disposals at 90.6% and led all players on the ground with six inside 50s.

GWS now face the Swans this weekend in the Sydney derby, and may welcome the inclusion of some veteran talent.

Steve Johnson missed the win over the Power, as Brett Deledio and Ryan Griffen are still out of the side with calf and ankle injuries respectively.

Brown believes when fit Stevie J will walk back into the side, and says the Giants need to get the balance between youth and experience correct for their tilt on the premiership later this season.

“The one thing I will say with the older players are important to have a bit of leadership out there,” Brown said.

“You’ve got to be careful with the Giants getting too young. They got flustered in the prelim final last year with a few bad decisions.

“I think Johnson definitely is a lock. And I would have Deledio in the best team as well.”