The Power will enter the elimination final as huge underdogs, up against a side whose president in McGuire has already publicly criticised the scheduling of next weekend's finals.
Nathan Buckley was unimpressed with the president's comments, suggesting he reeled in his focus to this weekend.
Indeed, if there's a lesson to be learned from the Power's rise in 2013 it would be that writing them off is a mistake.
Port has already clawed its way back against Adelaide (twice), West Coast and the Sydney Swans to register stunning victories this year.
They're the second best final-term club in the AFL behind Hawthorn.
Gray told AFL.com.au his side had great belief in its upset-causing ability.
"We've shown at times that our best footy can match it with the better sides," Gray said.
"It's finals footy, so we're going to have to be on top of our game for the whole game.
"We know that if we can perform at our best defensively, we'll be right in the game.
"That'll be the key – if we're to win the game we need to bring four quarters of effort and hold up defensively."
Gray entered this week under an injury cloud having been a late withdrawal from the Power's one-point loss to Carlton last weekend.
The club pulled him from that match citing quad tightness, but the 25-year-old insisted he had fully recovered.
"No dramas – I got through training yesterday no worries so I'm ready to go," he said. "I felt really refreshed this week ... just looking forward to getting out there on Saturday.
"I was a bit sore last week and heading into the weekend, so they thought it'd be best just to have a rest and a bit of a freshen up.
"'Harts' (Hamish Hartlett) has had a couple of weeks so he'll be the same and obviously 'Bobby' (Alipate Carlile) as well – it should hold us in good stead."
Like so many of his teammates, including veteran forward Jay Schulz, Saturday night will be Gray's first taste of finals football.
He played five games in his debut season of 2007 when Port reached the Grand Final, but wasn't selected after the home and away season.
The Power haven't seen finals action since.
"It's been a long five or six years that we haven't played finals footy, so everyone's just really excited and up and about as you can imagine," he said.
"I remember little bits and pieces [from 2007], I wasn't a member of the finals campaign though, I didn't play at all.
"Schulzy's been around 10 or 11 years and this will be his first final, so it'll be a special occasion for him, like the rest of us who haven't played finals.
"He's had to wait that little bit longer…I think he's that extra bit excited."
While coach Ken Hinkley urged his players to "embrace every second", Gray said training had remained the same at Alberton.
Given the Power enjoyed a 35-point win over the Magpies in round 14, they seem to be sticking to what works.
Time will tell whether it works again.
Twitter: @AFL_Harry
