Trouble pumping up, they said he refereed to Mikel as a monkey and also swore at another Chelsea player, officials of the sky club aint taking things soft, investigation currently going on over this claim.

The race-row that has engulfed Premier League referee Mark Clattenburg intensified further on Wednesday as two Chelsea players claimed they heard him call teammate Mikel Obi a ‘monkey’.

It has emerged that the pair of unnamed stars say this is what happened during their match with Manchester United on Sunday — but the official categorically denies making any racist comments.

Clattenburg has been accused of saying to Mikel, ‘Shut up you monkey’ as he booked him for dissent as well as calling Juan Mata a ‘Spanish t***’ in their 3-2 defeat at Stamford Bridge.

Mystery had surrounded what Clattenburg actually said to Mikel – until these allegations were made Wednesday morning.

But a source close to the referee told The Sun, “He said nothing of the sort – and he will fight this all the way.

“There is a lot of noise on the pitch and the players could have easily misheard.”

Meanwhile, Chelsea’s race case against Clattenburg is in serious danger of collapsing completely after it emerged that the club have employed independent lawyers to investigate the claims of their players.

The club are expected to conclude their internal investigation into allegations that the referee racially abused Mikel and swore at Juan Mata.

The external lawyers will then provide Chelsea with legal opinion as to whether their case will be successful. Despite issues over the available evidence, Chelsea remained robust ...Source