 Born in Moaña, Pontevedra, Aspas was brought up through local RC Celta de Vigo's youth system, and made his debut with the first team on 10 December 1999, aged 17, in a meaningless UEFA Cup tie against S.L.Benfica in Lisbon (Celta had already won 7–0 in the first leg, and he came on as a substitute for Benni McCarthy in the 1–1 draw).On 23 November 2003 his first La Liga game came, a 0–2 home loss against Athletic Bilbao; during that season, which ended in relegation, he also appeared in an infamous 0–5 derby loss to Deportivo de La Coruña also at the Balaídos.