Dundee striker Benjamin Kallman faces three or four weeks out after undergoing knee surgery.
Manager Jim McIntyre was encouraged by the Finn's partnership with Kenny Miller when the former Scotland striker scored in a 1-1 draw against St Mirren last time out, but Kallman will miss Saturday's trip to face Hibernian.
McIntyre said: "Unfortunately Benji Kallman has picked up an injury and is having surgery. It won't be too long, it's just a cartilage operation.
"So that was a disappointment after a positive performance between the two of them.
"But, if you put the ball in the right area, Kenny will score goals. So that is something we have worked hard on, making sure we are getting plenty of deliveries into the box and equally trying to make sure we are getting enough numbers in the box to cause the opposition problems."
Roarie Deacon is also out of Saturday's trip to Easter Road after suffering a recurrence of a thigh injury.
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