Ed Vickers-Willis knew he was facing a long stint on the sidelines when he crashed into a goalpost late in North Melbourne's round seven win over Sydney. 

The first North trainer on the scene feared Vickers-Willis had broken his right leg, but the defender sensed he had injured his posterior cruciate ligament, having missed the second half of 2017 with a grade-one tear of the same ligament.

Vickers-Willis knew he had done more damage this time, as he felt his knee hit and then twist around the goalpost.

He just hoped his anterior cruciate ligament remained intact.

"When you do your PCL your leg kind of sags a bit because its job is essentially to push the tibia forward, and when I was sitting on the ground I could see that it was sagging," Vickers-Willis said.

"But one of the trainers came over and he thought I'd snapped my leg because there was this big dint.

"Funnily enough, when I was sitting there some of the Sydney players were having a look and playing doctor a bit, saying, 'No, definitely it's a PCL, it's a PCL.'

"I was in a bit of pain and I knew it was significant. My thoughts going to the bench were, 'Just please don't be an ACL'."

North's doctors quickly ruled out an ACL rupture, but told Vickers-Willis his season was almost certainly over.

They diagnosed PCL and lateral ligament tears, which scans subsequently confirmed.

Leading sports surgeon Julian Feller operated on Vickers-Willis' knee soon after, following which he spent about three weeks on crutches and a further month in a knee brace.

Vickers-Willis was able to take his mind off the day-to-day drudgery of rehab by throwing himself into his commerce degree at Melbourne University.

Halfway through his course, the 22-year-old is locked in a friendly rivalry with teammate Jamie Macmillan, who recently completed the same degree.

"It can actually get the competitive juices flowing," Vickers-Willis says of his studies.

"Jamie Macmillan was telling me how good his GPA (grade-point average) was the other day. I don't know if I can catch him but it makes me want to do well at uni and gives me something to aim for."

Vickers-Willis can now see some light at the end of his rehab tunnel too.

Feller was happy with how his knee had healed when Vickers-Willis had a three-month check-up on Monday.

The next day he ran for the first time since his operation on a weight-bearing treadmill, then on Thursday he appeared on the training track to do some skills work away from the Roos' main group.

Vickers-Willis is on track to return to full training in mid-November and hopes to complete a solid block of work before Christmas.

Being able to run again has made his return feel so much closer, while watching his teammates vie for a 2018 finals spot has made him hungry to be part of a similar tilt next season.

The 190cm defender had been one of the Roos' most improved players over the first seven rounds of this season, showcasing an ability to play on smalls and talls and an increasing confidence to fly for his marks.

His mishap against the Swans continued a wretched run of injury that has limited him to just 14 games in four seasons at Arden St.

As frustrating as this has been, Vickers-Willis is eyeing 2019 with bolstered confidence.

"The really promising thing for me is I did find that confidence this year to fly for a few marks and I really felt that it was a good platform for the back half of the year to start cementing my spot, to find more of the footy, take more of those marks and play on some better opposition," he says.

"So looking to next year I know I've done that. Pre-season is not about finding my feet and seeing whether I belong at AFL level or finding a spot in the team, I know that if I'm fit and in form I'll be able to find a spot. 

"Now it's just about building on that really and going to that next level."