The Blues were 1-0 winners against the Premier League title favourites after Serbia international Branislav Ivanovic scored a first-half winner at Etihad Stadium.
You have to improve every day if you want to win the title
Chelsea are two points behind current leaders Arsenal, and Luiz, who is yet to win the English top-flight crown, wants the Blues to continue to work hard in the title race.
“We need to keep working hard and keep our feet on the floor,” Luiz told Chelsea’s website.
“It was just one more game and three points. You have to improve every day if you want to win the title.
“When you play against a strong team like Man City you can feel the importance, but in terms of the table it’s just another three points, that’s the truth.”
Earlier on Wednesday, Blues winger Hazard insisted that Chelsea are aiming to win the Premier League title this season.
“Lots of people thought that we would just set out to defend,” Hazard is quoted in The Sun. “But it was the opposite.
“We analysed City’s style of play very well before the game and we came along to win.
“The discussions we had in advance were all about winning. The manager said, ‘Don’t defend, you are here to attack and score goals’. He said the same to all our attacking players.
“We really did things in fine style. The three points will be important in the title race.
“We are aiming to win the league. It won’t be easy, but we won’t give up, we have the qualities needed to do it.
“Let’s see what happens between now and the end of the season.”
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