Chelsea manager Roberto Di Matteo condemns Twitter 'cowards' after Mikel is forced off social site by abuse 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. Chelsea were keen to stress today there was no currently no evidence that the racist abuse of Mikel had come from their own supporters. But they promised lifetime bans for those involved if that proved to be the case.