The result means that Conte's men have now lost their last three competitive matches in a row, with the other defeats seeing them miss out on both the FA Cup and the Community Shield to London rivals Arsenal.
"We must focus on working very hard with these players," Conte told BBC Sport after today's game. "As for the transfer market, the club is trying to do the best.
"I am not worried, I am ready to fight with these players. I repeat - it is important for us to concentrate on our work, to be focused every day in training and to try to work in our best way. No excuses."
Next up for Chelsea is a tricky trip to Wembley to face Tottenham Hotspur next weekend.