The Brazil defender made a celebrated return to Stamford Bridge on deadline day in a €40 million deal.
L'Equipe says negotiations began with PSG refusing to do business, particularly president Nasser Al-Khelaifi.
PSG chief Patrick Kluivert was happy to see the deal happen, but Al-Khelaifi wasn't interested.
Luiz was becoming increasingly desperate and eventually spoke to the president to urge him to take Chelsea's offer. In the end, Al-Khelaifi relented and allowed Luiz to go.
A close friend revealed: "As soon as he knew Chelsea was going to bid, he told us he was very motivated to return."