The former skipper has forced his way back into the first team in the past couple of months and was set to play a major role as one of the few players the Heart have with previous finals experience.

But the 2010 Joe Marston Medallist and former Glory skipper suffered a hamstring strain at training on Wednesday and won't make the trip to Perth to play in Sunday's elimination final.

Coach John van' t Schip, who could be in charge of his last game for the club, said 19-year-old Brendan Hamill will come in to replace Colosimo, who is 14 years his senior.

"Simon injured his hamstring on Wednesday. It is a big loss and we can make a big deal about it," van 't Schip said.

"But Brendan and Curtis (Good) showed that they are capable of playing at a very high level and now they have to show it together. It's a great challenge.

"We hope if we go through he (Simon) can be available for the next game but first we have to make sure we win this game."