Brazilian striker Charles netted the only goal of the game on his debut for Eibar to defeat former side Malaga at La Rosaleda.
The 33-year-old left the Costa Del Sol club earlier this summer after two seasons to join the Basque side and his header from Jose Angel’s cross just before the hour settled the tie.
The former Celta Vigo man had the ball in the net in the third minute but it was ruled out for a handball, while Juanpi went closest for the hosts in the first half.
Charles was a constant threat and should have scored after the break but fired straight at goalkeeper Roberto, on loan from Espanyol, before breaking the deadlock.
Ivan Alejo and Takashi Inui both went close for the visitors late on but one goal was enough for all three points.