DANIEL Wells is likely to miss North Melbourne's game against Carlton on Saturday night, and could also sit out the crucial clash against the Sydney Swans the following week.

North coach Brad Scott told reporters on Wednesday that Wells had recovered from the corked quad that sidelined him against Essendon last Saturday, but had since developed soreness in the Achilles tendon that ruined his 2015 season.

Given Wells' importance to North, Scott said the Roos were not about to risk him until he was back to full fitness.

"We probably thought we'd get to a stage where if we had to unload him due to another injury or for whatever reason, his Achilles might get a little bit sore again," Scott said.

"His Achilles is just not quite perfect, so I think you can all imagine how cautious we're going to be with that.

"It's possible he might play, but if he doesn't do enough on the track – he's got some tests to pass before we even risk him today – so unless he's absolutely perfect it will probably be the match committee's call just to leave him out for another week, maybe two.

"We're really optimistic and we're being potentially overly cautious and probably frustrating 'Wellsy' a little bit because he's missed so much footy, but we're determined not to turn this into something that could be more serious."

Wells worked away from North's main group at the start of Wednesday's training session, participating in stationary kicking drills with injured pair Jed Anderson and Taylor Garner.

Veteran defender Michael Firrito will come straight back in for North against Carlton after being rested last round, but Mason Wood (concussion) and Sam Wright (ankle) will have to pass fitness tests before being considered for selection.

Scott said Wood had "recovered incredibly" from his heavy landing after taking a strong pack mark against Essendon.

"He went to the VFL the next day, did his running on Monday, has consulted all the experts, and the experts have suggested to us that even though the incident can look pretty severe, sometimes you can recover really quickly," Scott said.

"So we'll still be very cautious with him, but the signs so far are really good."

However, the news was not so good for key defender Lachie Hansen in his recovery from a concussion suffered in the VFL two rounds ago.

Scott said Hansen still had lingering concussion systems and would not resume full training until he had fully recovered.

North played an extremely tall team against Essendon last round, with Majak Daw and Wood being added, at times, to the Roos' familiar key-forward mix of Drew Petrie, Jarrad Waite and Ben Brown.

Scott was unsure whether Daw would hold his spot against Carlton despite an encouraging two-goal performance against the Bombers.

However, the Roos coach was confident the 25-year-old had a promising long-term future at the club, pointing out that – barring "Boomer-like" longevity – 33-year-olds Petrie and Waite were "closer to the end than the beginning".

Aaron Black is another North forward who has struggled for opportunities behind Petrie, Waite and Brown in recent times.

But after a difficult 2015 season, Black has made a highly encouraging start to 2016, kicking 14 goals in the first five rounds of the VFL for Werribee.

"It's been fantastic. He's looking really dangerous, working really hard. He took a long time to get over a shoulder reconstruction, but he's looking terrific at the moment," Scott said of Black.

"'Blacky' is posing more and more (selection) questions for us all the time.

"We're in a good position with our talls where we can continue to pick the guys who are in form."