Carlton coach Brendon Bolton has confirmed the Blues will be without skipper Marc Murphy for about a month with the ankle injury he suffered against Geelong.

Kade Simpson will take up captaincy duties in his absence, starting with Saturday’s clash against Brisbane where Carlton will be looking for their sixth win of the season.

Murphy and Liam Sumner (foot) drop out of the side that upset the Cats, with Nick Graham and Ciaran Byrne earning call-ups.