But a premiership will remove any doubt about whether the move is wise or not from the Cats' perspective.

The 302-game veteran joins Patrick Dangerfield, Joel Selwood, Mitch Duncan and the up-and- coming Nakia Cockatoo on the first tier of talent on the Cats' list.

It's a frightening combination for opposition midfielders to contemplate with Dangerfield, Ablett and Cockatoo all damaging one-on-one players when thrown forward Dusty Martin-style as well.

This should give Cats coach Chris Scott the range of options forward of centre he craves, but mere talent won't be enough to move them from contenders to premiers.

While Dangerfield has proven himself to be a champion in either role, kicking 45 goals in 2017 and proving the difference when he played as full-forward in the semi-final against the Sydney Swans and round 17 against Hawthorn, Ablett is assumed to be capable of being that type of player.

Ablett has only once kicked more than 40 goals in a season, back in 2010, his final year at Geelong, when he kicked 44 majors playing as a midfielder.

That was mainly because his work has been required in the engine room, where he carried rising Suns through the initial phase of their careers but it's sobering to remember he has kicked just 28 goals in his past three seasons.

However, imagining him as a goalkicker doesn't require the left side of the brain to be overworked.

Still, assumptions are dangerous, particularly in an era when talent counts for less than complete buy-in to the game-plan from the entire list.

So, getting the forward line to do as much defending as attacking appears, as it has been for much of Scott's time at Geelong, the coach's biggest challenge.

Ablett, Tom Hawkins and Dan Menzel are not known for their defensive pressure so the Cats will need them to lift in that area as well as ensuring Lincoln McCarthy, Cory Gregson, Brandan Parfitt and Cockatoo are fit and available to tackle the problem.

The Harry Taylor as a forward experiment can end now with key defender Tom Lonergan retiring so Hawkins can play solo in a similar vein to Jack Riewoldt at Richmond this season.

Hawkins has been a great player but he turns 30 in July so he needs to get fit and perform to keep the emerging Wylie Buzza at bay.

Ablett's presence will also have a flow-on effect in the midfield with Scott Selwood and Sam Menegola best placed as defensive midfielders.

Cam Guthrie, who was given No.29 when Ablett left, might play midfield as well despite playing his best football in defence, as brother Zac, Zach Tuohy, Tom Stewart, Jed Bews Jackson Thurlow and Jake Kolodjashnij make the backline as crowded as the 5.04pm from Flinders Street.

In reality, a move to the Gold Coast might have been a good option for one of those youngsters but no Cat could be convinced to leave Geelong as part of the Ablett trade, a mindset Suns' coach Stuart Dew will need to change in 2018.

Duncan's importance as a line-breaker will increase with the departure of Steve Motlop to Port Adelaide and the Cats must either recruit someone to fill that void or train one of their midfielders up.

All that analysis presumes Ablett can maintain the unbelievable standard he once set beyond the age of 34.

If anyone can the champion can, but he has played just 34 games in the past three seasons with the Suns, dominating when fit and available but too often sidelined due to injury.

Ablett says he can play every game in 2018 but so does every footballer when the Spring Carnival is on the back page.

The Cats will need to manage the veteran wisely so he is at his best whenever needed most but they will also need him to play regularly so he can gel quickly with his new teammates, with only five former Cats remaining from 2010.

That's the type of quandary his presence creates. But as a relatively cheap buy, in both trade and financial terms, for a team that has lost its past two preliminary finals, the risk is worthwhile.

And Ablett is a different person to the one who left the club in 2010 as the game's undisputed king. He is more team-oriented, more mature and more aware of what he can and needs to offer to his teammates.

The biggest challenge for Ablett, Dangerfield and Selwood from now on is not performing well as individuals but being the type of characters that can support their less gifted teammates to be the best they can be in whatever role they are asked to play.

After all Ablett has six club best and fairests, nine All-Australians, two flags, two Brownlow medals and is a five-time winner of the AFLPA MVP.

He has nothing left to prove as an individual except this: can he be part of a Cats side that becomes known once again as a great team, rather than a side full of great individuals.

If Ablett can make Geelong a better team in 2018, it will be one of his greatest individual performances.