"We've been below our standards and against a Watford team you can't even get away with 10% off. But today some players were 30 or 40% off the standards they've set. They've let the group down; they've certainly let the fans down, definitely.
"I want to design a football team that wins games. It's something I'm obsessed with and, at the minute, we're not doing that.
"There's surgery needed and we're going to make that surgery and see where that takes us."
David was talking to BBC Radio Sheffield.