He told ITV1: "It was an incredible game, a strange game too. We had total control for so long and then gave it away in the last part of the game. We did show resilience to win the penalty shootout. We had control for 75 minutes and have to give Coventry a compliment for what they did in the last 15 minutes. We have to improve. We talk a lot about this. First you have to put yourself in a winning position but then you have to take it over the line. In these moments we are making mistakes and not keeping our responsibilities."
On whether there is a problem with his side's mentality, the Dutchman replied: "We can't say this group doesn't have the right mentality because they showed character today, but in the final part there was a lack of discipline. We have to keep the ball, keep making passes, go for goal and then also be strong in defence. It's about communication and we have to improve on this."