 Following the Uruguayan's relegation, he returned in the 2–1 Libertadores win over Táchira for then play in the derby against Universidad Católica on 20 April which was 1–1 draw where receive another free-kick goal, now from Juan Eluchans.However Castillo was chosen by Gallego to play the Superclásico against Universidad de Chile after an acceptable match in the prior 1–0 win to Santiago Morning at Estadio Nacional, same stadium where would play the Chilean most important derby and the prior elimination of Colo-Colo in the Libertadores after loss 3–2 as home against Cerro Porteño where played Prieto and receive a 27-yard free kick winning goal of Jonathan Fabbro in the 88th minute when Colo-Colo drawing qualify to knockout stage.Finally on 30 April during the derby, Colo-Colo freshly opened the score the 64th minute with Miralles' score but "The Owls" sorted it during the last three minutes with a penalty goal of Gustavo Canales nearly saved by Castillo in the 87th minute and two minutes later after Diego Rivarola's header that sneaked up in the Uruguayan's second post to put the final victory.