Third-year key defender Daniel Nielson will become the seventh North Melbourne debutant this season on Sunday against Fremantle.

Nielson has endured a long wait to taste AFL action after being taken by North at pick No.25 in the 2014 NAB AFL Draft, but the 21-year-old was told ahead of training on Thursday that he would finally make his debut against the Dockers.

The Eastern Ranges product's first season at Arden Street was a write-off after he ruptured his left anterior cruciate ligament late in the pre-season, and he played eight senior VFL games on his return last year.

Nielson had a delayed start to 2017 after his pre-season was disrupted by quad troubles, but the 194cm defender has performed some outstanding shut-down roles for the Roos' VFL affiliate Werribee this season, particularly over the past month.

The 21-year-old has a fierce competitive streak that makes him a tough opponent in one-on-one duels, but he has also improved his ability to come off his man and help out of his fellow defenders, with intercept marking becoming more and more a part of his game.

Nielson is the last of the Kangaroos' three-man 2014 national draft class to debut, following the first AFL games of Sam Durdin (round three) and Ed Vickers-Willis (round five) earlier this year.

Mitch Hibberd, Declan Mountford, Braydon Preuss and Jy Simpkin have been North's other debutants in 2017.

Nielson represented Vic Metro in the 2014 NAB AFL Under-18 Championships and finished third in the repeat sprint at that year's Draft Combine.