think it is very sensible.For an 18 year old with so few 1st team matches played, he seems entitled. He wants the guaranteed EPL money, but wants to delay hia move. This does make any sense to me as we are crying out for a starting CB. It is the perfect opportunoty.
How many other teams would start an 18 year old Centerback?
which means it's probably not his decision but a combination of club, agent and good advisers.