Gaffers View: Brentford home (1-1)(4-3)
The Bees made a mockery of their league one status and matched Birmingham throughout the game. They took the lead with just 20 minutes left and on 90 minutes they looked like progressing.
But in injury time Kevin Phillips popped up with the equaliser and then Blues went onto win 4-3 on penalties.
McLeish said: 'Brentford were superb, well organised and battled. I thought we were out the cup.
'But, when you have the hunger and desire to keep going right to the end, I have to salute the players.
'We put together three or four passes together for the first time for the goal. We lacked creativity and imagination before that.
'That made it look like we wouldn't score but Kevin did what he does best, we're in the hat and that's what counts.
'We're in the quarter-finals and it's all part of the development of the club.'