"I think it was a bad day at the office," said McLeish. "We are extremely unhappy and disappointed to lose, especially the way we started the game.
"If we lose goals the way we did today, it doesn't matter if it is Man City or an amateur team you are playing against, you will still lose goals if you don't organise at set-pieces.
"To lose the goals the way we did - it was comedy cuts. Needless to say we will be on the training ground this week working on that. It was horrendous defending."
The defeat means that the Midlands side are now eighth in the Premier League table, while Manchester City move to the top of the pile, two points clear of local rivals Manchester United.