*Club domestic league appearances and goals, correct as of 04:32, 8 March 2024 (UTC) ‡ National team caps and goals, correct as of 04:32, 8 March 2024 (UTC)
Born in Madrid, Boñar started his career as a midfielder with local side Club Deportivo Metropolitano, listing former Brazilian international Kaká as one of his idols growing up.[2][3] After moving to Atlético de Madrid in 2013, he transitioned to a central defender, and took to his new position well - playing at a youth level higher than his peers.[3][4]