KIEREN Jack doesn't have the heart to gloat about his AFL Grand Final success to his old man - unless he starts boasting about how good a rugby league player he was.

The Swans co-captain realised a dream in 2012, helping beat Hawthorn in his first big dance with the Swans for the coveted premiership.

The victory was just as sweet for him as it was for his father, Balmain legend and former Australian full-back Garry Jack, who had twice played in grand finals - 1988 and 1989 - but lost both.

Jack Jr, the eldest of three boys, was only a toddler at the time, but he's heard enough tearful stories since to know how much it hurt his father to walk away from a decider empty-handed.

"He was rapt to be able to compete in grand finals," the 27-year-old said.

"But to not get the job done, to lose in extra time, and the heartbreak of two grand finals, it was something that really sticks with him.

"So to be able to win in 2012 was amazing for not only me, but him as well. He could enjoy that.

"The great thing is, I get another opportunity to do it again."

That opportunity comes on Saturday at the MCG - and, again, versus the Hawks.

A win would give the Jack family flag No.2 and Kieren a 100 per cent grand final strike-rate in the top grade - something his father could only dream about.

"I don't rub it in - unless he starts making some smart-alec remarks about how good a player he was," he laughed.

"Then I'll bring it out."

Having struggled to come to grips with the game in his early years, the All Australian midfielder said he never imagined the day he'd lead out the Swans on grand final day.

"It's been an incredible journey," he said.

"When I got rookie listed to the club (in 2005), that's when I felt like I was quite behind the eight-ball compared to kids who had been drafted and in the system for a while.

"The game patterns and running patterns of an AFL midfielder, that probably took me a couple of years to really develop.

"But I think I've found my way now."