'Clever' Diego Costa leaves Arsène Wenger worried about Arsenal damage

• 'Costa got two of our players sent off in last two games,' says Wenger• John Terry says Chelsea have not given up on top-four finish Arsène Wenger labelled Diego Costa clever for the part he played in Per Mertesacker's early dismissal and bemoaned the "emotional damage" inflicted on Arsenal in their latest defeat by Chelsea, after an opportunity was missed to return to the top of the Premier League. Mertesacker was dismissed for a professional foul on Costa, who was racing on to Willian's...