Chelsea's Italian head coach Antonio Conte gestures to Chelsea's Spanish defender Cesar Azpilicueta (L) after the English Premier League football match between Chelsea and West Bromwich Albion at Stamford Bridge in London on December 11, 2016. Chelsea won the game 1-0. / AFP PHOTO / Adrian DENNIS / RESTRICTED TO EDITORIAL USE. No use with unauthorized audio, video, data, fixture lists, club/league logos or 'live' services. Online in-match use limited to 75 images, no video emulation. No use in betting, games or single club/league/player publications. /
Costa, Chelsea’s top scorer with 14 league goals, is thought to have been dropped after a training-ground row with fitness coach Julio Tous.
There are also reports he is the subject of an eye-watering offer from an unnamed Chinese club, but Conte said he had only been absent at the King Power Stadium because of a back injury.
“I repeat the truth because I like to tell the truth and not lie,” Conte told BT Sport.
“Diego stopped training on Tuesday because he felt a pain in his back and from that moment he didn’t train during the week. For this reason, he wasn’t available today. This is the truth.”
Costa, 28, is reported to have received a contract offer from China worth £30 million ($36.5 million, 34 million euros) a year.
But Conte said: “I don’t know anything about this.”
Asked if he would need to speak to Costa and owner Roman Abramovich to resolve the situation, Conte replied: “If there are problems, I prefer to solve the problem in the changing room and not during the press conference.
“If, and I repeat if, there are problems.”
Chelsea host Hull City in their next league game and Conte said it was too early to say whether or not Costa would take part.
“It’s very difficult to tell this now,” said the Italian.
In Costa’s absence, Conte aligned Eden Hazard as a central striker, flanked by Willian and Pedro Rodriguez.
Wing-back Marcos Alonso scored twice and Pedro also found the net as Chelsea bounced back from their 2-0 defeat at Tottenham Hotspur to go seven points clear at the summit.
“You guys made up the story,” Alonso told the BBC when asked about Costa.
“Diego wasn’t feeling well because of his back. He’s very happy and will have a great enough season at Chelsea.”
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