The striker ruptured his Achiliies against Birmingham City back in February and is now out of contract.
"I'm hoping to give Leon a little cameo role, perhaps 15-20 minutes," said Chris Coleman to the CT. "He's not ready for anything more than that, but it will be good to see what he can do.
"We've got him fit, he's been training well but now he needs to get a couple of 90 minutes under his belt. 
"When he's done that and we see how he reacts, I'll sit down with the medical team and if we think everything's OK we can talk about putting pen to paper."