Poblete was born in Santiago,[1] but began his football career as a youngster with Cobresal, based in the mining town of El Salvador.[2] He made his first-team debut on October 25, 2014, as a second-half substitute in a 3–2 defeat away to Universidad de Concepción in the Primera División, and made four substitute appearances in the 2015 Clausura,[3] including the penultimate fixture of the season in which Cobreloa came back from 2–1 down to beat Barnechea 3–2 and clinch their first Primera title.[4] He played increasingly regularly over the next two seasons, but when Cobresal were relegated in the 2016–17 season, Poblete remained in the top flight, joining Unión Española on an 18-month loan.[5] He appeared in all but one of the 2017 Torneo de Transición matches – half as starter, half as substitute – and contributed to the team's runners-up placing.[1][3]
