White has been subbed out of the previous two games after missing rounds 19 and 20 with a groin issue.
The 27-year-old didn't train outdoors on Monday or Tuesday but veteran Kane Cornes had no doubt he'd line up against his old side.
"He'll play. We've been fortunate to manage him over the past month or so, but come this time of the year there's no real managing of players - it's just everyone out there's fit to go," Cornes said.
"I'm really confident with what he'll be able to deliver and he'll be fine to play a full game on the weekend."
Cornes also said the inexperience of the Power's playing group would serve as no excuse this September, tipping it to "make an impact".
Port rocketed from the depths of the AFL ladder in 2012 to earn a finals berth last year, beating Collingwood in its elimination final before narrowly losing to Geelong the following week.
The side that beat the Magpies last year contained just eight players with previous finals experience.
White, Jarman Impey, Jack Hombsch, Jake Neade and Jared Polec are likely to be the only players making their finals debuts against the Tigers.
It will be Cornes' 17th final, equaling the Power's finals record.
He said that although the group was still learning, it could cause some damage this finals series.
"It's a different experience for us now with the home final and the added pressure and expectation that that brings," he said.
"To be the third youngest list or whatever we are and to be playing finals it's just a great experience for all of them, but whilst we are that, we're not here just to make up the numbers.
"Anytime you play finals it's a genuine opportunity … we need to have a full on crack and the guys are pretty determined to do that.
"We expect to make an impact and that's what we'll do Sunday."
Cornes warned a dip in output anywhere on the field on Sunday would likely have dire consequences.
Rather than talking up contested possession or composure under pressure as the most important aspect of finals football, the 31-year-old veteran said a perfectly rounded game won matches.
"There's no just one area you need to focus on [during finals]. Offence, defence, around the footy, the way you start the game – all areas you need to be eight or nine out of 10 to be able to compete.
"If you let yourself down in any of the areas you'll probably get beaten.
"You probably get away with it in the home and away season, being down for a quarter or for 20 minutes, but that won't cut it on Sunday.
"The group's in a really good position; we feel really confident with the way we're playing and our brand of footy should stand up on Sunday."
Twitter: @AFL_Harry
