David Luiz has told his Chelsea teammates to stop playing up.

Chelsea have been dogged by controversy over the past year, with captain John Terry hit with an FA ban for racially abusing Anton Ferdinand and Ashley Cole landing himself in hot water for an offensive Tweet.

Central defender Luiz feels it is now time to prove Chelsea players can be positive examples for the club's young fans, as well as successful ­footballers.

"I try to assert myself in a positive way, always trying to help," Luiz told Brazilian newspaper O Globo. "I'm trying to show what I can be, what I can add - not only for the team but for the club.

"Always try to understand the spirit of a club and what we represent. We are the mirror of our team on and off the field," added Luiz.

"I have the job I always wanted and I thank God every day for it. We are privileged for the things we have in our careers. ­Sometimes, a smile changes the life of a person, a couple, a family.

"People sometimes ask 'why are you so happy?' and I reply 'why aren't you?'. I am in love with ­Chelsea. I defend the club's colours with pride and love."