Career
Born in Eibar, Gipuzkoa, Oyarzabal joined Real Sociedad"s youth setup in 2011, aged 14. On 20 September 2015, Oyarzabal scored his first senior goals, netting a brace in a 5–0 away routing of Civil Defense Mensajero. On 8 February 2016, Oyarzabal scored his first goal for Real Sociedad in the 5–0 away success over RCD Espanyol.
Six days later, shortly after having extended his contract until 2021, he netted a brace to help defeat Granada CF 3–0 at the Anoeta Stadium.