The Scottish striker went down in the friendly against Manchester City and broke a bone in his leg as well as damaging knee ligaments.
MacLean fell awkwardly after trying to win a header and the extent of his injury was only revealed three days before the start of the season.
But the former Rangers hitman is keeping in positive mood and hopes that the injury will improve him in the long-term.
"Yeah I’m gutted," MacLean told Footymad about his four to six month absence. "It’s gut wrenching to be out but you get injuries as a footballer but hopefully I can come back stronger.
"It’s all part and parcel of being a football player; you have to take the highs with the lows. You have to remember the good times but it’s a test of character about how you come back from the lows as well so hopefully I can come back as not only a stronger person but a stronger player as well."
Despite the horrific news for the player, fans and the club's management team, MacLean is desperate to bounce back and thanks those who are rallying around him for keeping him upbeat.
He added: "You have to keep your chin up but at times it’s pretty hard and you have to do what you can but everybody’s been supportive, all the boys and the family have been terrific so got to keep that going really and I don’t see why I can’t make a full comeback.
"The surgeon who has operated on my knee has done a good job so fingers crossed that I can get back in the side and start scoring goals."