IT SUDDENLY dawned on Lewis Johnston that his time as an AFL player could grind to an uneventful end.

His best chance to stake his claim in the Adelaide line up and secure a contract beyond 2013 took a serious hit when, a week after Taylor Walker seriously injured his knee in round five, Johnston injured his.

A reconstruction wasn't needed, but the injury would sideline him for two months.

Injured and out of contract at season's end, it was during his recovery that Johnston realised a lacklustre return could spell the end of his career.

He admitted to AFL.com.au that the thought of "flipping patties" in his hometown in rural South Australia didn't appeal to him.

"It was during that time that it clicked that if I didn't pull my finger out and play good footy towards the end of the year, next year I'd probably be flipping patties at the local service station in Port Pirie," Johnston said.

"I just realised there was only eight weeks to go in the season and thought, 'I'm running out of time here'.

"I always try and do extra training, but I probably sharpened up with my recovery.

"I had a couple of quiet games, but I was pretty happy with my good performances."

His good form since breaking into the Crows' line up appears to have done the trick. AFL.com.au understands the club is on the verge of re-signing the promising 22-year-old.

Coach Brenton Sanderson has previously promised a new contract "without question".

Known as a prodigious set shot at goal, Johnston said he was most proud of his defensive development in 2013.

His average of three tackles a game was easily the best of any key attacking Crow.

"I still feel like I've got more to get out of myself, but at least I've experienced what's expected at the top level," he said.

"It's good to have the confidence that I can perform at that level too now that I've actually played a couple of good games.

"My competitiveness has improved, my second efforts and defensive pressure has probably improved the most out of everything.

"The goals will come if I keep improving in those areas."

North Adelaide will hope the goals flow freely during the upcoming finals campaign, with its star forward cleared for SANFL action.

Johnston's a product of the club, having started his junior career with the Roosters' under-15s as a 13-year-old.

With all Crows in the SANFL to play for the club's reserves side next year, this will be the last time Johnston can play in a Roosters jumper.

"I want to go back and play for North Adelaide because it'll be my last opportunity to play for them and they've done a lot for me in the years I've been at the club," he said.

"I'll do whatever [North Adelaide coach] Josh [Francou] wants me to do for him and the team to try and win the flag, if that's playing a defensive role or in the ruck, I'll do what I have to do."

Johnston was full of praise for Francou, crediting him as having the "biggest influence on my career".

"He knows what works and he's known how to get the best out of me," he said.

"My improvement as a player has increased more in the last two years under him than it did during my three years at Sydney.

"I want to play good footy for him."