 In 2008, at the age of 17, Sastre debuted in the Spanish 2nd-tier level LEB Oro, with Bàsquet Inca, where he played two games, before signing his first professional contract with Bàsquet Mallorca.One year later, Sastre agreed with Cajasol, where he would make his debut in the Spanish top-tier level Liga ACB, despite that he was loaned in his first year to Cajsol's affiliated team, CB Qalat of the Spanish 3rd-tier level LEB Plata.Sastre played in Sevilla for five years, before signing with the Spanish club CAI Zaragoza.