JARRAD Waite has completely transformed the way he plays in the past three rounds, adding a strong defensive focus to his trademark strong-marking game, North Melbourne coach Brad Scott says. 

Waite is set to play his 200th AFL game on Saturday night against former team Carlton, having crossed to North in last year's free agency period.

Scott said North had been "really happy" with Waite's contribution in his 15 games at Arden Street, particularly in the wake of the hugely disappointing loss to Gold Coast in round 14.

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"He's been our equal-third highest goalkicker this year, 16 games I think is his max in the last four years and this week he'll play his 16th for us with still a bit of the season left to go," Scott said.

"But most importantly for us it's not just his goalkicking output, he's completely turned around the way he plays in the last three weeks.

"The last three weeks he ranks No.5 in the competition in pressure (acts) and that's just a different Jarrad Waite to what we've probably seen in the past and his teammates are really acknowledging that.

"He's a really important part of our side now regardless of his output on the scoreboard." 

Scott said Lachlan Hansen (hip) would be available for North's clash against the Blues after returning from a two-week absence in the VFL last weekend, but would need to train well to force his way back into the team that comprehensively defeated the Brisbane Lions last Saturday night. 

Hansen had surgery on both hips at the end of last season after missing six of North's last seven games in 2014, including all three finals.

Despite the key defender's latest setback, Scott was hopeful Hansen would not be plagued by hip issues for the rest of his career.

"He had pretty major surgery last year on both hips and he just aggravated that a little bit, but it's still infinitely better right now than it was this time last year," Scott said. 

"The diagnosis at the moment is it's a minor aggravation and it should be fine." 

Daniel Wells' immediate playing future is much more clouded, with the midfield star's hopes of returning in time for the finals diminishing by the week.

Achilles tendon soreness has sidelined Wells since round two and he underwent minor surgery earlier this month in an attempt to overcome the lingering condition.

Scott said Wells had been increasing his training loads since the surgery but his return date remained unclear.

However, the Roos coach said the 30-year-old would almost certainly need to play a VFL match before he came back into the AFL.

"We're still pushing really hard to get him back before the end of the year, whether that's really soon or towards the latter rounds we're not sure," Scott said. 

"He's been out so long he'll need to play footy at a lower level, whether that's a significant match simulation session at training or VFL footy he'll need to do a fair bit of that before he's available for AFL selection."

Scott said Lindsay Thomas could start as North's substitute against Carlton after performing the role "really well" against the Lions.

He also said Leigh Adams was close to making a decision on his future after being sidelined for most of this year by the side-effects of recent concussions.

"I think it's getting to the point now where Leigh's been able to have all the appropriate tests because we just couldn't test him until he'd fully recovered from the short-term concussion (he suffered in the VFL)," Scott said.

"We're really hopeful that we'll get the results of that really soon and we'll be able to announce it."