It is Richmond's first finals appearance since 2001.
More than one teammate has noted that while Richmond veteran Chris Newman has had to wait more than a decade for his first taste of September, Vlastuin, 19, has only waited for 23 weeks.
"Everyone has been saying how lucky I am, how fortunate," Vlastuin said on Wednesday.
"I followed Collingwood growing up, so there were plenty of finals with them.
"But then 'Newy' has waited 13 years, I think ... I couldn't imagine that."
Vlastuin is enjoying the build-up to his first final, but admits the growing excitement among the Tigers faithful has caught him off-guard.
"It's a lot more full-on and a lot more fans than I thought there would be," he said.
The Blues beat the Tigers by 10 points in round 21 - Richmond's most recent loss. Vlastuin said this time, Carlton will not take the Tigers by surprise.
"We made a good start and they fought back," he said.
"We're definitely not going to underestimate them again."
Vlastuin said the squad was nearing peak fitness for the must-win final, set to be played in front of a packed house at the MCG.
"A couple of weeks leading up to that game (against Carlton in round 21) we were training pretty hard," he said.
"All the boys were pretty sore.
"The last couple of weeks, we've backed that off a bit because of finals.
"Getting the body right and little tweaks in the game plan, stuff like that - hopefully we'll be flying."
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