Chelsea allowed their best player to leave the club when they sold Diego Costa to Atletico Madrid, says Filipe Luis.
The Blues saw the Spain international depart over the summer after a falling out between the player and manager Antonio Conte.
It ended a hugely successful three-year spell at Stamford Bridge for Costa during which he won two Premier League titles and the League Cup.
In the two title winning seasons he scored 20 Premier League goals and it was that that marked him out as the best player at Chelsea, according to Luis.
‘Diego is a huge player,’ said the Atletico Madrid defender, who spent the 2014-15 season at Chelsea.
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‘Best player for me [at Chelsea] is him because he scores a lot of goals and important goals.
‘I think he came back to Atletico because Chelsea couldn’t keep him because it’s his desire. He really wanted to come back to Atletico.
‘He was happy here. He did his job really well. His most important desire was to come back.’
While Costa has returned to Atletico Madrid, he is unable to play until January due to the Spanish club’s transfer ban. It means he will play no part tonight when Chelsea host Atletico in the Champions League.
‘It is frustrating seeing him playing like an animal, but he can’t play,’ said Luis. ‘It’s just a month until he can play with us. He’ll help us a lot. I don’t have any doubts about it.
‘He knows the club, he knows the way we play. He has already adapted. I know it was difficult times for him and for Chelsea. Now everybody’s happy. We want to see him play and happy again.’