Chelsea boss Jose Mourinho is angry over Diego Costa's yellow card issued during last night's win at Burnley.
Costa scored on his league debut as Mourinho's team recovered from conceding an early goal to brush Burnley aside at Turf Moor.
But the 25-year-old was cautioned by referee Michael Oliver for diving in the first half even though he appeared to be brought down by Burnley goalkeeper Tom Heaton.
Mourinho said: "It was a penalty. The linesman made a mistake.
"We have all explained to him [Costa] what we want and what people in the Premier League like and don't like. We want it calm with fantastic attitude, competitive but clean and polite.
"The kid was obviously frustrated to be booked and I hope he doesn't get any more unfair decisions.
"I think Oliver had a very good game and unfortunately the linesman didn't support him well at that situation."
