Costa, Oscar in training ground row

Chelsea stars Diego Costa and Oscar had to be separated by teammates as a training ground clash threatened to turn into an ugly brawl, according to reports.

Costa reportedly reacted angrily to an aggressive challenge from Oscar, who was said to be furious with a previous tough tackle from the notoriously temperamental Spain striker.

A newspaper claimed "the pair squared up and had to be pulled apart by their shocked teammates before it turned into a physical scrap".