The Italian bad boy saw red in the 36th minute for an outrageous
chest-high challenge on Dinamo Kiev's Goran Popov.
It gave City a mountain to climb after losing 2-0 in the first
leg in Ukraine.
And although they pulled one back through Aleksandar Kolarov,
the Eastlands men could not turn the last-16 tie around.
City chief Mancini said: "It's a problem because Mario can be a
fantastic player.
"But when he does stupid things like tonight it's difficult for
me, for him and the team. Am I angry? What do you think?
"I didn't see the foul but I'm disappointed because this was a
difficult game and you can't have a stupid red card like this.
"It was tough but if it had been 11 v 11 we would have scored
two or three goals.
"With one player less and two goals down it became very
difficult. But the other 10 were fantastic for 60 minutes.
"Is he a frustrated man? I hope so because with 11 we would have
gone into the quarter-finals."
Mancini hinted he may axe Balotelli from his squad for Sunday's
showdown at Chelsea.
The pair are likely to have talks at Eastlands today but
Balotelli's red-mist moment left supporters fuming.
And there were claims he clashed with a group of Kiev fans
outside the ground after the game.
City defender Vincent Kompany added: "It's difficult to comment
on what happened but with 10 men it is difficult."
Seeing red: Mario Balotelli made his side's task
all the more difficult with a silly red card in the first
half
