The Blues attempted to sign the Argentina international at the start of the month but Benfica turned down a string of offers, adamant he will not leave unless his £105million release clause is met in full.
The Premier League side are now back in for the 21-year-old however with The Telegraph reporting there is firm belief at Stamford Bridge that they can wrap up a deal before Tuesday’s transfer deadline.
TYC Sports in Argentina meanwhile reports that Chelsea’s new offer is thought to be €100m (£87m) plus a player of Benfica’s choosing heading in the opposite direction.
Fernandez meanwhile was eager to make the move to Stamford Bridge earlier this month with agreeing personal terms even at this late stage in the window not thought to be a problem.
Fernandez’s stance is said to have changed however with reports in Portugal this week claiming he is happy to see out the season at the Estadio da Luz with Benfica boss Roger Schmidt not expecting the player to leave.
Asked if he was confident of Fernandez staying, Schmidt said: ‘Yes. When you see Enzo playing for Benfica you see a very happy player, in great shape.
‘He’s not thinking about anything else. I’m not expecting to lose any of our regulars, and that’s why I see very focused players and I hope this stays that way’.
Benfica also want to raise Fernandez’s release clause to €150m (£132m) to block any potential transfer this month.
Chelsea have already made six signings in the January window with Mykhailo Mudryk, Benoit Badiashile, David Datro Fofana, Andrey Santos and Noni Madueke arriving on permanent deals and Joao Felix on loan at a cost of £160m.
The Blues saw a £55m bid for Caicedo rejected last week with Arsenal also turned away after making a £60m offer on Friday.
Both clubs could return with improved offers in the coming days with Brighton boss Roberto De Zerbi not ruling out a late exit.
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