Chelsea Drop Unsettled Costa  (Sky Sports)

Diego Costa has been dropped from Chelsea's squad to face Leicester after a row with a club fitness coach, according to Sky sources.

It is understood he has not trained for the last three days after he was the subject of a £30m-per-year offer from a club in the Chinese Super League.

Sky sources understand the Spain striker has become unsettled by the approach from China, which would make him one of the highest paid footballer in the world.

And it comes as a major blow to Chelsea as the league-leaders look to get their Premier League title bid back on track following defeat to Tottenham last time out.

Costa has been in superb form this season and instrumental to Chelsea's rise to the top, currently sitting as the division's top scorer with 14 goals.

And Sky Sports football expert Graeme Souness believes this could derail Chelsea's title bid.

"This is the very last thing Chelsea need. He is playing out of his skin. They lose him and all of a sudden they are not going to win the Premier League," Souness said.

"If sense prevailed maybe he could stay until the end of the season. There has to be a way around this where everybody can be happy."

Costa joined Chelsea from Atletico Madrid in a £32m move in 2014 and the 28-year-old has scored 50 goals for the Blues in all competitions.