Luiz and Costa in training at the end of last season

David Luiz thinks Antonio Conte is punishing him because of his friendship with Diego Costa after he interceded on behalf of his former team-mate during his dispute with the Chelsea head coach last season.

The defender was dropped from Chelsea’s squad for Sunday’s Premier League win over Manchester United and made to train on his own on the morning of the game after querying some of Conte’s tactics in a stormy session at their Cobham training base last Thursday.

Like the rest of his team-mates, Luiz did not respond to Conte’s onslaught, but was sidelined in training the following day and made to watch from the stands at Stamford Bridge.

Luiz went to the training ground on his day off yesterday for some treatment on