WE'VE previously had "premiership ruckman Shaun Grigg", now will Richmond's traditional full-back David Astbury wear the same title come Saturday's final siren?

The Tigers have had different ruck combinations in its two most recent Grand Finals (Nankervis and Grigg in 2017, and Nankervis and Ivan Soldo in 2019), and due to a serious knee injury to Soldo, have opted to play the dour Astbury as relief ruckman during the finals.

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It was a surprising decision, and one which raises questions about the structure of the Tigers' backline without one of its most consistent players.

Fellow defender Nick Vlastuin gave afl.com.au an insight into how it came about.

"After his knee injury (missing rounds five to 17), Dave kind of came in as the eighth back. Without him for a lot of the year, we just had seven backs, with Noah Balta being the main key, then Dylan Grimes, myself and Nathan Broad," Vlastuin said.

"Dave coming in just gives us another number and it means we don't really lose him completely out of the backline. He's just a good player so you can't keep him out.

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"Without him, we – Grimes, myself and Balta – were finding we were playing a lot of game time, because if the opposition were playing tall up forward, we couldn't get off. Now Dave covers when we need to go to the pine.

"We know Toby (Nankervis) is a workhorse, but even he needs a rest, so Dave will go up and play ruck when Toby's cooked as well. So, we don't really lose him when he goes into the ruck, he's just playing as an extra back. It makes life easy." 

Nankervis put in a powerful performance in the six-point preliminary final triumph over Port Adelaide, becoming the first player to record at least 10 hitouts and 10 tackles in a V/AFL final and taking several important fourth-quarter marks in defence.

"He was super in that last quarter. When he took one mark, I said 'Leo Barry, you star!', being an idiot out on the field," Vlastuin said.

"His last quarter was super, and even 'Lynchy' (Tom Lynch) in the last minute or two dropped behind the play. We knew with a big key down there – who wasn't allowing them to run and jump at it – our tall guys would have free rein at it. He was unbelievable."

Reciting famous commentary aside, Vlastuin said he is quite the talker throughout a match, finding it keeps him better engaged in the game.

Vlastuin's focus will need to be razor sharp if Geelong superstar Patrick Dangerfield spends time up forward, where his powerful marking and game nous can turn momentum quickly.

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"It really depends where Dangerfield is in the forward line. He's a superstar player, so if 'Grimesy' is there and he's free, I'll try and put 'Grimesy' on him, so I don't have to," Vlastuin said with a laugh.

"They've got a lot of good players up there as well, so no matter who you play on, you've got to keep a close eye on them. 'Danger' is a very, very good player, so hopefully he's up there in the midfield running around somewhere rather than deep forward."

Levity aside, Vlastuin spoke with passion about the club's decision to wear black warm-up tops for the entire season, in a nod to the Black Lives Matter movement. Players around the league kneeled before each round one match, but the Tigers have continued with their own acknowledgement.

"We just wanted a way to make it not a one-week thing. The media can pick up and drop off things really quickly, but it was really important to us because we have so many Indigenous players who have been very good for our football club for so long," Vlastuin said. 

"The club does an enormous amount of work in that space through the KGI Institute, so it was really important to us to keep that front of mind."