Born in Elche de la Sierra, Albacete, Belencoso started playing as a senior with amateurs Deportivo Rayo Cantabria.

From 2002 to 2008, following a brief spell in Portugal, he competed mainly in the Segunda División B, representing at that level Real Jaén, Mérida UD, CE L'Hospitalet and CD Baza.

Aged 27, Belencoso reached Segunda División for the first time in the 2008–09 season, signing with local Castile-La Mancha club Albacete Balompié.

[1] He made his debut in the competition on 31 August 2008, coming in as a late substitute in a 2–1 home win against Sevilla Atlético,[2] but only scored twice[3][4] in the league over the course of two full seasons.

[8] He made an impressive start to his First Division League adventure, netting twice and providing two assists in a 6–2 victory over Sun Hei SC on 3 September.