Collingwood has announced two changes to its lineup ahead of Saturday's semi final against the Crows at Unley Oval.

Alison Downie has been omitted from the side that defeated the Bulldogs in an elimination final, while Tarni Brown will miss due to illness.

Charlotte Taylor and Erica Fowler return to the lineup as the Pies take on the league's most formidable opponent.

Adelaide narrowly defeated Collingwood in round four, claiming a five-point victory.

IN: Charlotte Taylor, Erica Fowler

OUT: Alison Downie (omitted), Tarni Brown (illness)