PORT Adelaide's Miles Bergman has been rewarded for his mature performance against Adelaide with the NAB AFL Rising Star nomination for round 21.

Bergman gathered 23 disposals and had four tackles and four clearances on Saturday night, but more importantly took a game-saving mark with seconds remaining as the Power held on to win an epic Showdown by four points.

The running defender was recruited from Sandringham Dragons with pick No.14 in the 2019 NAB AFL Draft but failed to crack it for a debut last season following a year interrupted by injury and the club's inability to participate in the SANFL in 2020.

The 19-year-old eventually ran out for his first game in round one this year and has gone on to play 19 of a possible 21 matches, helping the Power in their push for a top-four berth.

Bergman is the second Port Adelaide player to earn a Rising Star nomination after Mitch Georgiades was nominated in round five.