The Power finished a disappointing 10th last year but will start narrow favourites against top-four fancies the Lions on Saturday after an impressive start to the season.
Five of the 24 games played between the 2004 grand finalists have been decided by less than a goal and Voss said it would be a tough ask for his side to get the points this weekend.
"I rate Port very highly. I think they've got a team system that they're putting in place and they're playing a style of footy that would suggest they're top-eight material," Voss said in Adelaide on Friday.
"They might not have earned the reputation of that yet, but I certainly hold them in that light with the way they're being coached at the moment and the way they're executing their game strategy."
Port Adelaide ran out convincing 48-point winners when the Lions last came to town in round 14, 2009.
The visitors trailed by just 14 points at the main break but lost their cool in a disappointing second half which saw Jared Brennan reported for head-butting veteran midfielder Josh Carr.
Voss said he hoped his players had been scarred by that loss and would use it as motivation this week.
"Whenever you get a beating - and we did get a beating here last year - you always have those little scars. Last year we had a couple (of big losses); one against Geelong and one here," he said.
"I felt that (intimidation from Port Adelaide) throughout the whole game, but they're just the mind games that get played. The Port players were able to get in our head and they've obviously noticed it, so it's something we've got to be mindful of."
The Lions have made three changes to the side that defeated Carlton in round two.
Tom Rockliff, James Hawksley and James Polkinghorne have been recalled in place of Brennan (suspended), Cheynee Stiller (omitted) and Jed Adcock, who has a torn quadriceps muscle.
Voss said Rockliff, Hawksley and Polkinghorne had all demanded selection against the Power.
"Their form in the pre-season and also in the early parts of the reserves that they've played has been exceptional, and Rockliff probably even more so than the others," Voss said.
"The three of them have demanded a position in the team and Todd Banfield did the same in round one. He was our bolter over the pre-season and then found himself playing round one and being pretty handy for us at the same time. Those three come in pretty comfortable knowing they're in pretty good form."
In-form forward Jonathan Brown has been instrumental in the Lions' perfect start to the season, but Voss said the forecast wet weather meant his side would be less reliant on Brown and recruit Brendan Fevola on Saturday.
"You only have to look at Browny's stats in wet weather … he goes okay, but with the weather it becomes even more important for our other players to be able to step up and make sure that they play a part.
"His 10 minutes in the third quarter last week were very important for us and he can lift a team, but that's almost like the cream on top. Everyone else is got to be able to do the work and if just expect Jonathan Brown to do it well Port is going to have a field day against us."
