Hawthorn have dropped Ryan Burton and St Kilda have axed veteran midfielder David Armitage for Sunday's AFL matches.
The Hawks say they are concerned about Burton's form after his round-one ankle injury and he is their third omission for the MCG match against Melbourne.
They already had dropped Kaiden Brand and Will Langford.
"We feel it's best for him (Burton) to have a game or two at Box Hill and, hopefully, regain some touch," said Hawks football boss Graham Wright.
David Mirra will make his AFL debut, James Sicily returns from suspension and Conor Glass will also return.
The Demons will give Angus Brayshaw his first senior game this season, while Dom Tyson is ill.
With Armitage out, the Saints have made four changes for their match in Geelong against the Cats.
Sam Gilbert, Tom Hickey, Jack Steele and Jack Lonie will return.
Jimmy Webster has a hip injury, while Josh Bruce and Nathan Wright are dropped.
The Cats have also made four changes, axing James Parsons.
Gary Ablett, Nakia Cockatoo and Cam Guthrie are injured.
They have recalled Mitch Duncan, Rhys Stanley, Jordan Murdoch and Jordan Cunico.
Essendon will give Matt Guelfi his AFL debut in the Etihad Stadium clash with unbeaten Port Adelaide.
He comes in for suspended defender Conor McKenna.
The Power have named Trent McKenzie and Karl Amon for Sam Powell-Pepper, who is serving a club suspension, and Dom Barry.
It is McKenzie's first game for Port since his move from Gold Coast.