The Blues have struggled to retain their Premier League title this season despite the west London side winning the top-flight crown so convincingly in Conte’s first season in charge at Stamford Bridge.
Chelsea FC finished seven points clear of their closest challengers Tottenham Hotspur last term after a 13-game winning run helped to separate the Blues and the rest of the chasing pack.
Conte offloaded Costa to Atletico Madrid last summer despite the Spain international scoring 20 times in their title-winning campaign to prove a key member of the Italian’s starting XI.
However, the pair had a fractious relationship culminating in his return to Atletico last summer following the arrival of Alvaro Morata in a club record £65m deal from Champions League winners Real Madrid.
Morata has struggled to fill Costa’s void given the Brazilian-born forward has a combative style suited to Premier League football.
Former Arsenal star Keown believes Costa’s departure is largely responsible for Chelsea FC’s struggles this term.
“Unfortunately, that strong will may have been his downfall,” Keown told the Daily Mail.
“For whatever reason, he clashed with Diego Costa and decided quickly that he did not want him in the squad. It’s clear they have missed him this season, and his absence may cost Conte his job. Maybe their next manager, whenever he comes in, should be someone more relatable.”
Chelsea FC are in fifth place in the Premier League table and 10 points behind Liverpool FC and Tottenham Hotspur.
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