Carlton has made four changes for Saturday's crucial clash with Port Adelaide at AAMI Stadium. 

As expected, Andrew Walker will return from a bout of gastro and Matthew Kreuzer is back from his calf injury. 

David Ellard and Jeff Garlett also come into the side. 

Brock McLean will miss the match after suffering a quad injury last weekend, while Nick Graham, Aaron Joseph and Nick Duigan have been omitted. 

Joseph, Duigan and Kane Lucas have been named as the emergencies. 

The match kicks off at AAMI Stadium at 4.10pm ACST.