Liverpool manager Jurgen Klopp is wary of Diego Costa's "world-class" talent as he prepares his team to face up to the in-form striker.
The Spain international scored twice against Swansea on Sunday to take his tally to four in as many Premier League matches and appears to have rediscovered his form after a difficult time in Jose Mourinho's last season at Stamford Bridge.
While Costa has his critics for his antics on the pitch and a reputation for playing the game on the edge, Klopp sees only a top talent his side need to stop, although he has scored just once in four appearances against Liverpool since arriving from Atletico Madrid.
"He is world class and that is the best thing football fans can say about you. If other supporters love you it is not a good sign," said Klopp ahead of their Friday night trip to the capital.
""He is a real warrior on the pitch, he uses his body all the time and that is a quality. He was nearly unstoppable against Swansea."
Klopp also holds new Chelsea boss Antonio Conte in high regard.
The 47-year-old won three successive Serie A titles with Juventus from 2011 before going on to manage Italy.
He shares many similar traits with Klopp in terms of his enthusiasm and involvement on the touchline, and the technical area could be as lively a place as the pitch on Friday.
However, Klopp insists they should not be compared.
"I don't know Antonio good enough to know why he is doing it - I know for myself and, as I've said a few times, it just happens to me," he added.
"He looks quite emotional, even when they don't score. Obviously he is involved in the game, but that's not the most important thing.
"The very important thing is he is a great manager, something like the 'Pep Guardiola of Juventus' if you want.
"He created their special type of play and had a very successful time there and with the national team.
"It is quite impressive what he has done until now, but I don't play against Antonio Conte."
Stamford Bridge was the scene of Klopp's first Premier League victory on October 31 last year when Liverpool came from a goal down to win 3-1.
They played each other in a tetchy and occasionally bad-tempered friendly on their pre-season tour of the United States during which Cesc Fabregas was sent off for a crude lunge on Ragnar Klavan and Reds midfielder Marko Grujic ended up in hospital with concussion after a clash of heads with Bertrand Traore.
There has been animosity between the two sides, and sets of fans, for the best part of a decade, but Klopp likes to think there is some form of mutual appreciation.
"I know about our respect for Chelsea and I am pretty sure from the other side there is exactly the same," he said.
"They've seen us playing and they know we are not easy to play and that is what I thought most about in the last two days and what I will think about because there is always a way to create moments which you are not expecting.
"The problem is they maybe have the same plan.
"They were champions two years ago and then had a difficult year and they changed their manager.
"Last season was not a Chelsea season and now they are back on track, so we need to be ready for a real challenge. "
Source: PA
