Ryder gave St Kilda's midfielders an armchair ride with his superb tapwork, had an aerial presence at both ends of the ground and booted two vital goals.

But what should have been the big Saint's proudest moment in a 257-game career - playing in his first finals win - turned to bitter disappointment after he suffered a season-ending hamstring injury in the dying seconds, contesting a boundary throw-in.

Amid the euphoria of St Kilda's first finals win for a decade, a tearful Ryder cut a forlorn figure on the bench.

In his first season at his third club, the 32-year-old ruckman has been a key component of the Saints' resurgence under coach Brett Ratten.

Ryder's absence in this Friday's second semi-final leaves St Kilda without one of its major weapons, as he and the equally versatile Rowan Marshall have formed arguably the AFL's best ruck combination this season. Marshall will have to do the bulk of the ruckwork against dual premiership Tiger Toby Nankervis, with youngster Max King providing some assistance in the forward half.

The likely replacement for Ryder is Josh Battle, who missed the elimination final with a foot problem.

Collingwood and Geelong also have big decisions to make about their ruck divisions ahead of Saturday night's first semi-final.

Struggling Magpie Brodie Grundy is a pale imitation of the ruckman who earned successive All-Australian honours in 2018-19.

Last Saturday night Collingwood recalled Darcy Cameron to share the ruck responsibility with Grundy, who spent long periods on the bench.

Grundy took two strong marks in the final quarter. But significantly, with the result hanging in the balance and just over a minute to play, Cameron was preferred to face off against West Coast's All-Australian ruckman Nic Naitanui at the final centre bounce.

The Cats are well aware of Grundy's match-winning capabilities, having dominated against them in last year's first qualifying final and earlier this season in Perth.

Geelong coach Chris Scott will not make the same mistake of leaving out Rhys Stanley as he did in last year's final.

Stanley made a solid return from a groin injury against Port Adelaide last week. The Cats are likely to recall Esava Ratugolea to support him as a ruck/forward option.

The Magpies' tactic of going with an extra big man worked well against the Eagles, adding potency to their much-maligned attack.

Mason Cox rekindled memories of his outstanding 2018 preliminary final with a three-goal first quarter and he will keep veteran Cat Harry Taylor busy.

Brody Mihocek, who remains unsigned for next season, booted two superb goals in a frenetic last term to finish with three majors and underline his value as a hard-working forward.

It was a superb start to the finals series with four hard-fought encounters.

Sadly for the Bulldogs and the Eagles, the post-mortems have already begun despite being eliminated by a combined total of four points.

For the Dogs, it was their second successive elimination final defeat and their record this season - having defeated only one team in the top eight (West Coast) - suggested they were not going deep in the finals series.

Their midfield, led by skipper Marcus Bontempelli, Jack Macrae, Tom Liberatore and Bailey Smith, is one of the best in the AFL, but last Saturday's heartbreaking loss underlined their weaknesses.

The tall forward combination of Aaron Naughton and Josh Bruce hasn't worked and they need a classy, quick small forward in support to put the heat on opposition defences.

Tim English has plenty of ability, but whether he will develop into the No. 1 ruckman the Bulldogs are hoping for is problematic. They also require a good one-on-one key defender.

The Eagles struggled with life in their Queensland hub and their early results reflected that.

Once they returned to Perth, they showed rapid improvement. But there is a heavy dependence on Naitanui gaining the ascendency in centre clearances and stoppages to feed a midfield that is one-paced.

While Josh Kennedy and Jack Darling remain potent forces in attack, Kennedy is in the veteran class and they need Oscar Allen to step up quickly.

Glenn Shirley, of Rose Bay, Tasmania, asks: Which things which have occurred in this weird season do you think will flow on into 2021?

The AFL finally has its night grand final and, given it, will be a ratings bonanza for the Seven Network, there will be immense pressure on the league to make the time change permanent next year (or at the very least, a twilight fixture).

Having a more flexible fixture with the potential to squeeze more games into a condensed period also appeals to the TV networks and the AFL, hence the push to retain shorter quarters - maybe 18 minutes with time-on, instead of 16.

Hopefully, the league returns to a day grand final and 20-minute quarters, but I fear not.

Email me: howardkotton11@gmail.com; Twitter: @hpkotton59.