Willie Collum has pulled out from refereeing Aberdeen-Hibs with a groin strain.

The official suffered the injury whilst overseeing Schalke's 2-0 win over Galatasaray in the Champions League on Tuesday.

He has now been replaced by Alan Muir for the Pittodrie fixture on Friday night.

Earlier in the week Rangers said they will submit a formal complaint about Collum following his display during their 2-0 victory against St Mirren.

Collum dismissed Daniel Candeias late in the second half after dishing out a controversial second booking to the Light Blues winger.

Rangers' appeal against the call failed, leaving the Ibrox club incensed.