Barcelona, Real Sociedad and Valencia qualified for the round of 16 in the Spanish King's Cup on Tuesday evening.Barcelona qualified after a hard-fought away win over third-tier Guadalajara, with two clean goals scored in the second half by Andreas Christiansen and Marcus Rashford in the 76th and 90th minutes.Valencia qualified by winning away from home against Sporting Gijon with a score of 2/0.Lucas Beltran and Danny Raba scored the visitors' goals in the 4th and 48th minutes.At the same time, Real Sociedad narrowly won away to Eldense 2/1.Sociedad took the lead with a goal from Luka Sučić in the 79th minute, and the hosts quickly equalized with a goal from Nacho Quintana in the 81st minute.The Basque team clinched the qualification ticket with a goal at a fatal time, scored by Pablo Marin in the 96th minute.Barcelona, Sociedad and Valencia joined Deportivo La Coruna and Elche, which qualified by beating Mallorca and Eibar, in two matches earlier on Tuesday.