The tension around Chelsea was believed to have been eased slightly once Jose Mourinho's increasingly tempestuous reign ended last month.

But today saw claims of a bust-up between two Chelsea team-mates during training.

According to a few reports, Diego Costa and Oscar had to be separated after some robust tackling, with the former said to be unhappy with a challenge from his colleague.

But the confrontation was then said to have been quickly broken up and laughed off.

Either way, Oscar has denied the claims via his Twitter feed:

For those who are talking to me and @diegocosta struggle today in training he's lying, he's one of my best friends and never fight 😉

— Oscar (@oscar8) January 7, 2016

And even if there was a minor clash, those types of incidents are commonplace on training fields as many pundits and ex-players often attest.