According to the Express, the Premier League champions were leading the chase and looked to be closing in on a deal after tabling a bid of £15.5m – and Napoli are allegedly willing to sell the Spain international.
However, they will now have to fend off Internazionale, as Roberto Mancini is willing to offer defender Juan Jesus in a swap deal for Callejon.
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Callejon scored 11 Serie A goals last season, and could be considered expendable at the Stadio San Paolo with Gonzalo Higuain the first-choice centre-forward for the Italian outfit.