NORTH Melbourne key defender Scott Thompson feared his AFL career was over at the end of last season.

The 31-year-old enjoyed a solid 2017 to finish ninth in North's best and fairest award, but a month after the season ended the Kangaroos had still not offered him a contract for 2018. 

Thompson was fully aware North was committed to a youth-based rebuild, having seen long-term teammates Brent Harvey, Drew Petrie, Michael Firrito and Nick Dal Santo delisted a year earlier.

As a restricted free agent, the 2013 All Australian had received interest from other clubs, but even if North delisted him Thompson's desire to remain a one-club player was so strong he wasn't sure he wanted to extend his career in rival colours. 

Fortunately, Thompson got the contract he had been hoping for from North during October's trade period, but he has not forgotten his brush with football mortality. 

"It was a nervous wait and a situation I'd never really been in. It was a new experience," Thompson told NMFC.com.au.

"You get a phone call and it's either them telling you, 'Look for a new job' or 'You've still got a job'. 

"So you do have to think about life after football, but it was great North gave me the call and gave me the nod for another year. 

"I played my 200th game (in round 23) and it must have been close to being my last game because (I had) six weeks of waiting and then (got) a nod. I think people probably don't understand that you don't sometimes get a 10-week liaison into life after football, it can just happen in a split second." 

Thompson understands North's need to rebuild following its finals appearances in 2012 and 2014-16, and accepts football has become a "business".

The Roos again ushered veterans off their list this season, delisting Lindsay Thomas, Sam Gibson and Lachy Hansen, while former captain Andrew Swallow retired despite being contracted for 2018. 

But Thompson says next year won't necessarily be his last season. 

"Everything has to fall into place. If I'm playing good football and the club wants me, I'd love to extend my career," he says. 

"I've still got really good football ahead of me. I'm a competitor and I never want to lose. You'd never say this is my last year either because that's the wrong mindset to go in with."