Paris Saint-Germain defender David Luiz insists he made "a good choice" swapping Chelsea for the Ligue 1 champions despite Jose Mourinho's insistence that the Brazilian's departure has strengthened the Blues.

Luiz endured an uncertain two-and-a-half year spell at Stamford Bridge, with lapses in concentration and defensive errors undermining his progress in west London.

Nevertheless, PSG opted to sign Luiz in the summer for £50m in order to partner him with Brazil teammate Thiago Silva as Laurent Blanc attempted to enhance his squad ahead of a renewed assault on progressing in the Champions League.

A war of words has since ensued between Luiz and Mourinho, who is convinced Chelsea are stronger since the departure of the 27 year old but the Brazil international is convinced otherwise.

"I made a good choice coming here," said Luiz. "I am happy to play in this team. Of course I smile a lot. I am a happy boy."

Chelsea followed the sale of Luiz with the signing of Diego Costa, Filipe Luis, Cesc Fabregas, Loic Remy and Didier Drogba, and have since set the pace in the Premier League this season, leading champions Manchester City by three points after 15 matches.

Luiz was often used in midfield during his final season at Chelsea in the absence of ineligible January signing Nemanja Matic but with the Serbian available for all competitions this term, Mourinho says his squad is much stronger.

"David did important things here, was always good professional and we will miss him as a good guy," he said. "But from a football point of view, we believe our squad is stronger this season than it was.

"In midfield, he was an physical guy and gave us important things, especially in the Champions League when Matic couldn't play. But this season, Matic can play in the Champions League so we don't lose that physicality.

"The fact we have Cesc Fabregas moves us in a different direction. It's something that our football needs and we want to go in that direction."