Tarrant and Hansen formed a formidable team with Drew Petrie in attack in the second half of last season as North stormed into the finals with a 10-2 finish to the home and away season.
But the tall trio was not as effective in this season's first three rounds. Tarrant has missed the past two games with a leg injury and Hansen was a late withdrawal from North's clash with Hawthorn last Sunday with a minor medial ligament strain.
In their place, Majak Daw and Aaron Black have put their cases for regular spots on North's forward line.
Daw came in for Tarrant in round four against the Brisbane and impressed with his strong marking in a debut cut short by concussion.
While Daw didn't have the same impact against Hawthorn and was substituted at three-quarter time, he still had three shots at goal in the third quarter and memorably ran down Shaun Burgoyne in the first quarter.
Black came in for Hansen against the Hawks and, in his first game since round 12 last season and just the fifth of his career, grabbed his opportunity with two goals, two goal assists and eight tackles.
Scott said Black would play against Port at Blundstone Arena on Saturday, with Tarrant and Hansen's selection chances dependent on their performances at training this week.
"Unless I'm comfortable with the level of training they've done and how they perform in the main session they won't play," Scott said of Tarrant and Hansen on Wednesday.
"We're in a fortunate position where we've got good key position players who can replace them."
Scott said North faced a balancing act between giving Black and Daw extended runs at AFL level to build their confidence and picking its best 22 each week.
"The bottom line is I've got my eye on a slightly bigger picture, but that's not at the expense of playing players in form," Scott said.
"So we'll just pick the best available and we're not too worried about exposing young players to AFL footy.
"We've got a lot of players who are in form. 'Blacky' and Majak are inexperienced but they're the best available right now to help us win."
Scott said North wasn't unlucky to be sitting 1-4 after five rounds despite its tough draw and narrow losses to Collingwood, Geelong and Hawthorn.
He said the team had let itself down with concentration lapses at crucial times in those games, but dismissed suggestions the Roos' delivery into their forward 50 was a problem, despite their AFL ranking of 16th for marks inside forward 50 this season.
"I think we rank fourth for scores (from) inside 50s in the competition," Scott said.
"We had 63 inside 50s (against Hawthorn), we scored at roughly 50 per cent on the weekend (and) generated 31 scoring shots.
"I think we're scoring OK. But could we do it better? For sure and we'll continue to work on that.
"But when we had Aaron Black playing his (fifth) game and Majak Daw playing his second we understand that they're going to make mistakes at times and we're going to make some mistakes kicking the footy inside forward 50 at times.
"But I think it's been a strength rather than a weakness."
Nick Bowen covers North Melbourne news for AFL.com.au.Follow him on Twitter: @AFL_Nick
