Girona have re-signed Brazilian midfielder from Manchester City on another season-long loan deal.
The 20-year-old made 15 La Liga appearances for Girona last season, but will hope to make more starts after all but one of those outings came from the bench.
Scottish champions Celtic had been keen to land Luiz, while Porto, Benfica and Fenerbahce were also linked.
But Girona won the battle before confirming his return via Twitter on Friday afternoon.
Girona finished 10th in La Liga last season and have started the new campaign with one point from two games.
They drew 0-0 with Valladolid on the opening day before being thrashed 4-1 by Real Madrid nine days later.
Luiz featured for City during their pre-season trip to the USA but he is yet to make his senior debut for the Premier League champions.