"We have to do more, we know that. But when you look at the players we have here, we should really be in the top 10.
"Except Arsenal, I've not seen a team that is better than us. For me, Manchester City can win against anyone. We must have the confidence to believe that, but the bad results we've had haven't helped."
City's form has also meant that the Frenchman has had to play in an unfamiliar role but he remains committed to the City cause.
"We've had bad results so we've not been able to play the way that the gaffer would like us to," said Sibierski, 29.
"I have to play like a defensive midfielder sometimes, like Joey Barton and Paul Bosvelt. It's not my position because I'm more of an offensive player but I'm happy to play anywhere for this team."