The versatile defender took a blow to the shin in the first half but played on during the second period before a massive swelling occurred after the game and he was rushed to hospital.
Our Head of Medical Facilities Dr Charlotte Cowie explains in this week's treatment table that Goran suffered 'acute compartment syndrome' where internal bleeding builds up pressure and can do enormous damage to the muscle.
The injury is similar to that suffered by Christian Ziege in the Boxing Day game against the same opponents in 2002.
"People might not know but he got an injury in the first half and played on for 45 minutes and showed a lot of courage," said Head Coach Martin Jol.
"It turned out to be a bad injury and he had an operation after the game. He will be out for quite a long time. So good luck to him for a quick recovery.
"It is a very difficult injury, after the game it looked like he had the match ball down his sock. It was horrific to see, he went to hospital and the doctors treated it so credit to them. I hope he will be back soon."
Martin reported that Erik Edman, Thimothee Atouba and Sean Davis are missing for the trip to Turf Moor to face Burnley tonight in the Carling Cup, but Edman and Atouba are making good progress. Anthony Gardner is back in training after a foot problem.
"We travel with 17 players and will pick the best team. We won't make a lot of changes although we have to make some.
"It was a difficult injury for Erik Edman but hopefully he will be back next week, Thimothee Atouba is not 100 per cent, but nearly fit. That is a good thing with Goran being out.
"Anthony Gardner trained again in the morning so hopefully he will be ready for selection."
Goran Bunjevcevic is facing a long spell on the sidelines after undergoing surgery following the Charlton game on Saturday.