ALEX Neil was frustrated that Millwall could not build on their impressive win over Derby County after slumping to a 3-0 defeat at Birmingham City.

The Lions had thrashed Derby 4-1 at The Den on Saturday but were brought back down to earth with a disappointing display at St Andrew’s.

Neil’s side conceded three soft goals inside 30 minutes, with Alex Cochrane, Max Bird and Jay Stansfield all finding the net. That was in sharp contrast to Saturday, when Millwall raced into a 3-0 lead inside 20 minutes.

To make matters worse, right-backs Tristan Crama and Ryan Leonard were both absent through injury, although Tairyk Arconte returned to the squad after a short absence.

“We are really disappointed we didn’t build on the weekend,” Neil said. “We’ve had a few challenges in terms of personnel. Consistency in terms of team selection and how we play is going to be important for us.

“At the moment, we feel as if we’re taking one step forward, and then we lose somebody, and then it’s one step back.

“Tonight was frustrating. The game got taken away from us in the first half because of our indiscipline, their clinical edge that they had in the goals that they scored and the chances we missed. And then from there, it was always going to be tough to get back involved in the game.”