Sebastien Larsson gave the hosts the lead after half an hour before Gabriel Agbonlahor equalised for Villa shortly after. But a late winner from Nicola Zigic sent the Blues into the semi finals to face West Ham.
The Frenchman said: “I’m very disappointed for the fans and very disappointed for the players because they played well and we were probably the better team on the whole. We deserved a bit more and it’s a shame that we made some silly mistakes the cost us the goals but that’s football.”