The Brazil midfielder only moved to Juve this past summer from Aston Villa, but has struggled for minutes.
La Gazzetta dello Sport says Luiz has confided to some friends that he is dissatisfied with the situation in Turin.
So much so that his agent, Kia Joorabchian, is already sounding out interested clubs in Spain and England to find a way out.
It also emerged this week that Juve sports chief Cristiano Giuntoli was in Manchester for talks with United and City about Luiz.
Giuntoli is insisting on a straight sale for Luiz next month, rather than a loan arrangement.
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