HAMSTRING tightness has forced North Melbourne youngster Luke Davies-Uniacke to miss the Roos' final game of the season.

The No.4 pick at last year's NAB AFL Draft was brought into the North line-up to replace Will Walker, who hurt his knee in last week's loss to Adelaide.

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But the hamstring issue will see Davies-Uniacke miss the Roos' clash with St Kilda on Sunday at Etihad Stadium.

Paul Ahern, who has performed strongly at stages this season for North through the midfield, has come in as his replacement.

The Saints will enter the game unchanged.

All eyes will be on North key forward Ben Brown in the clash, with the spearhead needing to kick seven goals to tie for the Coleman Medal with Richmond gun Jack Riewoldt.

St Kilda v North Melbourne at Etihad Stadium, 4.40pm AEST

LATE CHANGES
St Kilda: No change
North Melbourne: Luke Davies-Uniacke (hamstring tightness) replaced in selected side by Paul Ahern

FINAL INTERCHANGES
St Kilda: Blake Acres, Jack Newnes, David Armitage, Jack Sinclair
North Melbourne: Nathan Hrovat, Luke McDonald, Paul Ahern, Sam Wright