Potters assistant manager Dave Kemp said: "He's just someone who came to our attention.
"We've invited him in for the week, but obviously it's a three-game week so it's not ideal to see him.
"He trained very well on Monday but it could be a long road before we make a decision.
"You have to be careful, because someone could look really good in a five-a-side game, but could be a million miles away from doing it in a real game."