Liverpool boss Jurgen Klopp has jumped to the defence of Diego Costa and claims the Chelsea striker is "world class".
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 during 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 needs to stop when the two sides clash on Friday night.
Costa has scored just once in four appearances against Liverpool since arriving from Atletico Madrid but Klopp knows he will be a real threat at Stamford Bridge.
"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 the 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.
"The very important thing is he is a great manager, something like the 'Pep Guardiola of Juventus' if you want," he added. "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."