"It will be a heavily watched game, also because it is our first meeting since the Champions League final," Cech told his personal website.
"We want to stay top which means we must beat Manchester (United)."
He added: "Every clean sheet is valuable - I am glad that we started the Champions League with a win.
"We wanted to start like that and that happened. We defended well and responsibly.
"Most of the Bordeaux shots went wide. From this point of view, I did not have much work, but on the other hand it was more complicated for me to stay focused throughout the whole game."