The deal looks to be a short term one which will take the popular McKenzie up until January.
McKenzie ruptured his Achilies against Birmingham City back in February but recovered to play the last five minutes of normal time against Swansea City last week. He is in the squad which travels to Blackpool today.
"I'm going to pull Leon in and put something in writing for him," said Chris Coleman to the CT. "I'll talk to him about the length of it and obviously the salary and everything."