On 25 May 2006, Costa's return to Benfica to play in the upcoming season was announced in a press conference. He had been released from Milan after both the player and the club reached an agreement to end his contract. Costa gave up of his €4.6 million per year contract with Milan after he had dreamt of his return to Benfica year after year. His return saw former Benfica and Portugal international Eusébio praise Costa's return. Costa's first match back saw him start in a 2006–07 UEFA Champions League qualifier against Austria Wien in August 2006. The return leg saw Costa score in his return to the Estádio da Luz in the 21st minute. Benfica would go on to win 3–0 and clinch a place in the group stages of the Champions League.