Joey Barton says he couldn't believe it when Chris Coleman took over at Sunderland – as he thought he was "better than that".
The 47-year-old resigned from his post at Wales so he could succeed Simon Grayson at the Stadium of Light.
Sunderland are bottom of the table ahead of tomorrow night's game against Aston Villa at Villa Park.
Former Newcastle United midfielder Barton told talkSPORT: "They have just set the record for most home defeats, they are bottom of the table, there's a disconnect with the owner. I didn't see him taking that job.
"I thought he was better than that. He must be getting weighed in to go there and been given guarantees to spend in January.
"Has anybody seen if he is all right? Has anybody checked to see he is all there (or) if he has had any problems with his mind or lost his senses?"
Barton thought Coleman's next job would be at a Premier League club.
"I thought he would he would have had an opportunity (in the Premier League)," said Barton.
"You have seen David Moyes go into West Ham, could he have taken that? Paul Clement is under pressure at Swansea, could he have taken that?
"West Brom, could he take that? Everton, could he have taken that?"