Former Chelsea midfielder Michael Ballack has praised manager Antonio Conte's handling of Diego Costa after the striker reportedly tried to force through a lucrative move to China this month.
Costa, the club's top scorer this season, was recently left out of the Chelsea squad with a back strain amid British media speculation of a row with backroom staff and a possible transfer to Chinese side Tianjin Quanjian.
The 28-year-old Costa, however, silenced doubters after the Spain international scored on his return in Sunday's 2-0 win over Hull City.
"With toughness, he (Conte) took him out of the squad, which was an understandable situation, if it was the back or not it doesn't matter," German Ballack, who spent four years at Chelsea, told British media.
"But also the answer's good from Costa. They are two really high-class professionals dealing with each other."
Ballack also felt players could be distracted by the current market situation but urged them to be wary of Chinese riches, saying the sums being offered were not normal.
"It seems to be another level since the guys from China disturbed the market a bit, and the brains of the players," the 40-year-old added.
"It's difficult for the club to put all the players back in line, all the players who get a crazy offer. It's numbers that we are not used to, even if in England there has been a lot of money involved for a while.
"I don't think it's normal, but hopefully we come back a bit to normal days."