Chelsea look to be back in the hunt for Juventus midfielder Paul Pogba.
New-boy Fabregas is expected to line-up with Nemanja Matic in Jose Mourinho's midfield next season.
But with Mourinho seeking to emulate his first success at Stamford Bridge, he appears keen to have at least two high quality options in every position.
Pogba is also being chased by Paris St-Germain who spend with apparent impunity due to their owners' deep pockets, bankrolled Manchester City and Brendan Rodgers' Liverpool, who are about to cash a huge cheque for the transfer of Luis Suarez.
The gap left by Luiz is looking increasingly likely to be filled by Kurt Zouma – the young French centre half who spent the second part of last season on loan at Saint-Etienne.
He is not expected to be pitched straight into the toughest Premier League games but is seen as a realistic option.
Also, with this potentially being John Terry's last season at Chelsea, there is hope he will get a chance to learn from one of the game's greats.
However, Gus Poyet's Sunderland are among those chasing a loan deal for the 19-year-old.
Meanwhile, new midfield signing Mario Pasalic is expected to spend the coming campaign on loan.
Pasalic enjoyed a breakthrough year a Hajduk Split last term and scored 11 times in 36 appearances to help his club secure a third-place finish in the Croatian League.
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