Former Scotland boss Eck - our third most-capped player ever - has now opened the door to a comeback.
McLeish said: "I know it is obviously eating at him and I think Craig (Levein) is trying to influence him to go back.
"I don't blame Craig for that at all. I'd probably do the same thing but it's up to Barry.
"Scotland have two hard games coming up against the Czech Republic and Spain.
"I know Barry would excel in the company of those teams but then he would have to come back and play away at The Emirates against Arsenal. It is a big ask for a player who is 32 - but it is up to him.
"He has been excellent for us. His performance last week against Liverpool was as good as I've seen from him. He was outstanding."