Chelsea playing hardball over Antonio Conte’s pay-off after his treatment of Diego Costa

Chelsea are haggling to get a discount on Antonio Conte’s pay-off because they feel the Italian cost the club millions of pounds with his treatment of Diego Costa.

The Blues have lined up Maurizio Sarri, Napoli’s coach for the past three seasons, to take over on a two-year contract.

But the unhappiness with Conte at Stamford Bridge – allied with a new financial reality at the Roman Abramovich-owned club — has seen them reluctant to pay up £9million for his contract’s final year.

The former Italy and Juventus boss won the Premier League title in his first season in 2016-17, then signed an improved contract until 2019.

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And although Costa scored 20 goals, a terrible second campaign for Conte started when the Italian informed the Spain striker by text last summer he was no longer in the manager’s plans.

After Costa returned to Brazil, Chelsea finally agreed a £59m deal to sell him to his former club Atletico Madrid. But the Blues were furious with Conte’s conduct as he badly hurt their negotiating position – and Costa’s displays at this World Cup show he was undervalued.

Jose Mourinho and his staff were paid off with £8.3m following his December 2016 sacking, to go with the £23.1m they received after the Special One’s first departure from the club in 2007 — a staggering total of £31.4m.

Chelsea want club legend Gianfranco Zola to join Sarri as an assistant and to overhaul the squad this summer after finishing a distant fifth as defending champions, 30 points behind first-placed Manchester City.