LONDON • Chelsea will attempt to withhold a portion of the £9 million (S$16 million) owed to Antonio Conte in severance pay on the grounds that his infamous text message to Diego Costa 12 months ago adversely affected his transfer value and cost the club millions of pounds.

The Times revealed on Friday that Conte is taking legal action against his former club after being sacked last week. The 48-year-old Italian won the FA Cup last season but could steer Chelsea to only fifth spot in the English Premier League.

He is claiming that the delay in resolving his future cost him the chance to take lucrative jobs elsewhere this summer, while Chelsea have yet to finalise the severance package that has formed a standard part of their managerial contracts for several years.

The club will argue through their legal team that Conte's actions in telling Costa that he was not wanted last summer cost the club millions in lost transfer revenue and therefore amount to misconduct.

Conte sent Costa a text message last June which included the words: "Hi Diego, Thank you, but you are not in my plans," after the player sought permission to return late for pre-season training.

Costa never played for Chelsea again after going absent without official leave and spending the summer in Brazil before eventually joining Atletico Madrid last September, although he was unable to play for the Spanish club until January because of their transfer embargo.

Atletico paid £57.2 million for Costa, but Chelsea claimed that they would have received far more for the forward without Conte's message leading to him effectively going on strike.

Conte's view is that his message was inconsequential, as Costa had already been told by the club last summer that he would be sold, having asked for a transfer on three previous occasions.

The former Italy coach also claimed that he was provoked by Costa, who had responded curtly to a previous text from the head coach asking all his players to do some fitness training on their own during the close season.

Costa, 29, had also been fined by the club and banned from training for two days by Conte the previous summer, having said that he did not want to play for him.

Conte has not spoken since being sacked by Chelsea nine days ago, other than in a statement issued through the League Managers Association in which he thanked his "friends" at the club for their help during two seasons at Stamford Bridge. He has been replaced by countryman Maurizio Sarri, who arrived from Napoli.

THE TIMES, LONDON