The Mirror says Mangala - a target for some the top clubs in Europe - has taken a step towards joining Chelsea by hiring Jorge Mendes as his agent.
Mangala was linked with the west Londoners in the recent summer window, and are reportedly keen to try again in January.
Manchester City considered a bid for the 22-year-old France international, who has a £40m buyout clause in his contract, in the last transfer window.
They instead bought Martin Demichelis from Atletico Madrid for just £3.5m on deadline day.
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