The Brazil international completed a return to Stamford Bridge on transfer deadline day this summer after Chelsea agreed a £32m fee with Ligue 1 champions Paris Saint-Germain.
Luiz won two French top-flight titles after he moved to the Parisian club in a £50m deal in 2014 after the centre-half was deemed surplus to requirements under Jose Mourinho.
The South American made a suspect start to his second Chelsea career after the west London side lost 2-1 to Liverpool before a 3-0 defeat by Arsenal in Luiz’s first two 2016-17 Premier League starts.
However, the 29-year-old has helped the Blues keep back-to-back clean sheets as part of a back three following victories over Hull City and defending champions Leicester City.
But Souness has warned Conte and Chelsea supporters that Luiz is unlikely to make drastic improvements to his game ahead of the twilight years of the Brazilian defender’s career.
“If it was going to happen for him, it would have happened by now,” Souness told Sky Sports on Saturday afternoon.
“He is guilty of over elaborating and trying to play in the wrong areas. He has got ability of a type. He is a good striker of the ball. I don’t see him as a reliable defender.”
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