Star Collingwood draftee Jaiydn Stephenson is set to sign a two-year contract extension after a sublime start to his AFL career.

The teenager was crucial in his team's upset win over Adelaide last Friday night, booting five goals to go with his 13 disposals in a near best-on-ground performance.

Stephenson's management and the Magpies had already been in discussions over a new deal, meaning he will be at the club until at least the end of 2021. Detailed negotiations will begin shortly.

The Magpies were delighted when Stephenson slid to pick six in last year's national draft, with some recruiters believing he was the best player in the pool.