Tell me, why would Jose Mourinho and Co. sell Luiz to a Premier League rival when—according to the Guardian—Chelsea reportedly turned down a £35 million offer by Barcelona for the Brazilian?
Doesn't make a whole lot of sense, does it?
According to the Guardian report, Luiz has been labeled "untouchable" by Mourinho during the transfer window, along with Oscar, Juan Mata and Eden Hazard. Barcelona's attempt to nab the talented 26-year-old was reportedly instantly shot down.
United manager David Moyes may believe that Luiz's doubts about receiving regular playing time at Stamford Bridge will fester, but the fact that Mourinho has basically tabbed Luiz as a core member of Chelsea would figure to be enough for Luiz to stay. He is indeed valued at Stamford Bridge, even though he isn't perfect.
Luiz does have a tendency to sometimes take risks on the back end (and sometimes get burned), but it doesn't appear to have changed the Blues' opinion of him. After all, his passing ability, ball interception skills and long shots make him a desirable player regardless. Even if he isn't the ideal player on the back end for Chelsea, as Moyes suggests, he still brings enough strengths to the table to overshadow his deficiencies.
If Mourinho turned down a £35 million offer from Barcelona, then turned around and accepted a £30 million offer from United, the manager would receive backlash at Stamford Bridge like no other. The move would not only be going against Mourinho's warm perception of Luiz, it would also be going against logic, plain and simple.
Unless United ponies up and offers a great deal more for Luiz (which may not even be worth it), I can't see Chelsea selling the talented defender. Some rumours make sense. Others just need to go away, for the sake of sanity. The latest rumour connecting United to Luiz is the latter.