"We need to not be over-confident. We have to realise we have a 3-0 lead from the hard work we put in right from the start of the game," he told the official site.
"Obviously we expect City to come looking for an early goal, because they need to start the process of trying to unnerve or get us on edge," he says.
"The first game had action at both ends and I felt we had the better of them. As with young players, with all players in fact, they don't convert all the chances. But we are pleased to have scored three and kept a clean sheet.
"We just have to be sensible how we go about the second leg."