West Coast champion Josh Kennedy was left feeling "numb" after producing his best goalkicking performance in almost seven years in the final game of his brilliant career.

Kennedy booted eight goals in his farewell game at Optus Stadium, matching his effort from round one, 2016, as the Eagles looked for their retiring star at every opportunity against Adelaide.

The dual Coleman medallist delivered for his team in a masterful goalkicking display, admitting it had become obvious early on that the Eagles would be doing everything to send him off with one last bag of goals. 

Captain Luke Shuey's early decision to look inboard to set Kennedy up rather going long to an open Jack Darling was the first sign of the players' focus, with premiership teammate Liam Ryan also looking to the key forward every chance he got.

"That was probably the moment where I thought 'boys we need to chill and win this game, and not just focus on me'," Kennedy said.

"The boys fed me a fair bit and there was probably a lot of ball that came my way that shouldn't have.

"But me and 'Boots' (Shuey) have played so much footy together that we kind of know what each other are doing, and sometimes it paid off, sometimes it didn’t."

Kennedy's first two goals came close to the boundary and almost 50m out, and the 34-year-old continued to hit them sweetly until a rare but critical miss late in the fourth quarter.

The emotion of the day got to him on several occasions, he said, running onto the field with his two daughters and being chaired through a guard of honour by senior teammates Shannon Hurn and Shuey to finish.

He paid tribute to the supporters after a season-high crowd 50,117 packed Optus Stadium for the occasion and produced a finals-like atmosphere with the game on the line late. 

"We as footballers, we're out there and we perform and it feels like the consensus is we give a lot to the fans," Kennedy said.

"But to be honest, they give us so much. They make our game great and they're the reason why we can play football.

"I've been so lucky over the course of my career with our fans at West Coast, and it brings a tear to my eye sometimes, just how much they actually give to you over your career. I can't thank them enough."

Kennedy said he looked forward to resting his troublesome knee, watching from the stands next year, and "giving my two bobs, probably messaging Simmo here and there".

Simpson, who coached Kennedy for 173 of his 293 games, marvelled at his premiership star's performance, which was the best goalkicking display by a player in their final game in the AFL era.

Melbourne's Fred Fanning, who booted 18 goals as a 25-year-old in his final game in 1947, is the only player in VFL/AFL history to kick a bigger bag in their last appearance.

"Can you imagine kicking eight goals in your last game? It will probably never happen again," Simpson said.