Chelsea fought bravely in the second half, with goals from substitute Alvaro Morata and David Luiz.
But that was not enough to prevent Chelsea losing on the opening day of the season for the first time for 19 years.
Conte made his first statement of the day before the kick-off – with his squad for the opening match of the season.
The Chelsea boss has made it clear he is unhappy with the depth of his squad.
And he went into the big kick-off with little-known Jeremie Boga, 20, making his debut and Kenedy, sent home in disgrace from the pre-season tour after his comments in China, on the bench.