PORT Adelaide forward Aidyn Johnson will remain with the Power until at least the end of 2019.

The 19-year-old has signed a two-year contract extension after making his AFL debut and playing five games in 2017.

"Physically, I’m feeling really good now after having trouble with injuries during my first season," Johnson said.

"Having had a taste of AFL footy this year I’m determined to earn a regular spot in the side."

Johnson was chosen by Port Adelaide with pick 45 in the 2015 NAB AFL Draft.

He had 14 possessions and booted two goals in his debut game against Carlton in round five. 

"His speed is a major asset and his pressure around the contest is at a high level," the Power's general manager of football Chris Davies said.

"His challenge is to take it to a new level in 2018."

With Johnson locked away, the Power are close to finalising their list for next season.

However, forward Jesse Palmer, veteran Matthew White and winger Jimmy Toumpas are yet to sign new contracts.