Micic has dislocated a shoulder and will have to see a specialist but left-back Evangelos Ikonomou will be available for United's visit, having recovered from the back problem which forced him off against St Johnstone.
Centre-back Scott Boyd returns to the squad after suspension but goalkeeper Mark Brown is still absent due to a fractured hand.
Dundee United welcome back midfielder Mark Millar for the trip to Victoria Park.
Millar returns after serving a suspension and full-back Keith Watson may also feature, having missed last week's loss to Motherwell with a knock.
But Gavin Gunning (knee) and Johnny Russell (fractured leg) remain on the sidelines.