BILBAO, Spain- - Brothers Inaki and Nico Williams scored to help Athletic Bilbao secure a 3-0 semi-final win over Atletico Madrid on Thursday and a 4-0 aggregate victory that sent the Basque side into their third Copa de Rey final in the last five years. Ernesto Valverde's team punished the visitors with clinical counter-attacks, starting when Inaki Williams struck in the 13th minute with a superb volley from his brother's cross. Inaki returned the favour to his younger sibling in the 42nd minute, setting up Nico for a simple close-range finish. Bilbao continued to dominate and Gorka Guruzeta wrapped up the win for the Basque side from a rebound in the 61st minute. Bilbao will face Mallorca, who beat Real Sociedad 5-4 on penalties in the semis, in the final in Seville on April 6.