City managed to beat the Premier League leaders 2-1 after Emmanuel Adebayor cancelled out his own goal and Carlos Tevez managed a match-winning free-kick.
Hughes said: “We had to show courage and bravery. When you are playing a team like Chelsea you need to believe in your own ability.
“Some sides give them too much respect, which just allows them to create opportunities and win games.”
Chelsea ace Frank Lampard had a penalty saved by Shay Given in the dying minutes of the game and Hughes believes the pressure got to the England international.
“Sometimes things happen that you don’t expect and I didn’t expect Frank to miss,” said Hughes.
“In fairness to him, I think he understood the importance of converting that chance, which brought extra pressure.”
