Isak, who joined Liverpool from Newcastle last summer for a record-breaking £125M, failed to make his mark at St. James’ Park on Sunday afternoon in what was a dire performance from the striker.
It was not a welcome return for the Liverpool star who was booed roundly all afternoon by Newcastle fans who feel like he betrayed the side when he departed over a year ago.
Liverpool boss Andoni Iraola said Isak “tried everything” and that the poor atmosphere was not a “big surprise” for him.
Speaking to OLBG, body language expert Stanton revealed that Isak was frustrated on his return and tried not to give his emotions away.
"Isak does something called lip suppression when he first arrives at St. James' Park. His lips are closed, pierced and slightly compressed. There's no arrival smile or anything like that from someone who is returning to his former home ground. He's very aware of the reception he's receiving and what is being chanted.
"The next thing I notice is that his eyebrows are slightly lowered, and he's looking downwards before entering the ground. This actually shows he wants to get away from the Newcastle fans as quickly as possible.
"He's trying to act like he's not bothered by it, but he clearly is. When people don't look around, they try to imply that they are not bothered and that they don't care. It wouldn't surprise me if he wasn't actually listening to any music at all!
“With Isak, he comes across as very guarded and doesn't want any of us to read his emotions. He's like a stone and doesn't want to project anything. No anger, no excitement, and no disgust.
"In terms of the way he is walking, it's quite purposeful. But he just wants to get away from it as quickly as possible.
"Overall, I would say that Isak is very aware of how he is thought of by Newcastle fans. He's clearly unhappy about it. Otherwise, he'd be displaying different emotions. I'd go as far as saying there are eight or nine consistent red flags of behaviour that tell us Isak is not happy on his return to Newcastle United."
Isak scored four goals in a difficult debut season for Liverpool and he must start to show his old self under Iraola as supporters begin to turn on him and his severe lack of goals.