Chelsea boss Roberto Di Matteo has slammed racist Twitter abuse directed at his midfielder John Obi Mikel.
The Nigerian shut his Twitter account earlier this week after receiving abuse via the social media network following Chelsea's midweek draw with Juventus.
The abuse occurred at around the same time Mikel deleted his Twitter account, although Chelsea insisted the 25-year-old had not been aware of it and had been intending to leave the social media site in any event.
Manager Di Matteo said: "His intention was to close the account anyway. So it was a good reason to close it.
"The social media world, especially Twitter - because it's anonymous and so on - it's a dangerous vehicle to express yourself.
"I don't think it's fair. If somebody has to express his opinion, he should put his face to it."
The abuse of Mikel occurred after his mistake helped Juve come back from 2-0 down in Wednesday night's Group E game, something for which the midfielder immediately apologised.
News of the tweets about him emerged on the same night Lazio fans were accused of directing monkey chants at Tottenham's black players in the sides' Europa League clash at White Hart Lane.
Di Matteo added: "There's a lot of campaigns against (racism) and we have to try our best to fight it in every possible way.
"We should try to make the people understand that it hurts other people, chanting and things like that."