Hislop insists the Sweden international has long lost the 'moral high ground' after his actions before releasing a statement over claims of 'broken promises' about being allowed to leave this summer.
Speaking on ESPN, Hislop said: "You don't go back to your former club to train. You don't miss pre-season. You don't stay away from the football club. And then in mid August claim a moral high ground!
"You've given that up. If that is what you are doing, do it and own it. But you don't get to turn around six weeks into it and claim some kind of moral high ground here. I don't understand Alexander Isak's position and that ridiculous statement on social media. I do not understand who is advising him.
"I cannot think of any way he could have got this more wrong. It's an absolute farce."