West Coast's Willie Rioli can't wait to continue his AFL premiership celebrations in the Tiwi Islands, having shared an emotional moment with cousin Cyril at the MCG on Saturday night.

Rioli has ensured his family name will continue to be associated with key moments in Grand Finals.

The forward's 28th goal of the season was far from his most impressive, a stumbling kick off the ground amid a goalsquare scramble, but it was almost certainly his most important.

Rioli was responsible for the Eagles' first goal in the decider and came after Collingwood kicked five consecutive goals to rattle the visitors.

The 23-year-old also played a vital role in Dom Sheed's match-winning kick, when he blocked Collingwood defender Brayden Maynard and allowed his teammate to take an uncontested mark.

It meant Rioli, who moved to Adelaide and famously shed 16kg in a successful attempt to show recruiters how hard he was willing to work for an opportunity at the highest level, followed in the footsteps of Cyril by capping a dream AFL season with a flag.

As teammates celebrated wildly in West Coast's rooms, Rioli walked outside to have a quiet word with Hawthorn's four-time premiership hero.

"It was pretty emotional," Rioli said at Melbourne airport on Sunday.

"He just congratulated me on the year I had and how he was happy for me.

"It's still sinking in today.

"It's been a long journey for me.

"I never thought I'd have the year I've had.

"To have this medal around my neck, it's all credit to mum and dad for that.

"'Simmo' (coach Adam Simpson) as well and the West Coast coaching staff."

Cyril Rioli was a sounding board and source of support for his cousin throughout September.

That was also the case in 2017, when Richmond's Daniel Rioli played a key role in the Tigers' drought-breaking premiership.

"I can't wait to take this medal home, up to the Islands, and go up there with mum and dad," Rioli said.

"Mum and dad are still a bit emotional about it but hopefully when they get back to the island they can readjust, have a think about it.

"It means so much to them."

Rioli explained his Grand Final goal was a little fortunate.

"Lucky enough it just hit my foot," he said.

"I tried to soccer it. Didn't really get the most purchase off it but I got a little tap on it."