Cech made a crucial intervention against Manchester United, is eager to back up the win against the Russians.
"It's always important to beat big teams for the confidence," Cech told chelseafc.com.
"We wanted to book a place at Wembley. We seem to have a special relationship with the FA Cup; we treat it with respect, every season we try to win it and we get something back.
"We have another tough game against City but it's a semi-final so you expect a tough game.
"We are not having such a fantastic season in terms of the league but it shows we can still beat the top teams and it gives us confidence to play another game on Thursday.
"We have another semi-final to book in the Europa League and hopefully we are going to go through."