Damião's senior breakthrough came in 2000, as he won the silver medal at the 2000 Ibero-American Championships in Athletics (finishing behind Brazil's Hudson de Souza) and came 31st in the short race at the 2000 IAAF World Cross Country Championships. He and de Souza repeated their placings at the 2002 Ibero-American Championships in Athletics. He appeared three more times in the World Cross Country short race in 2004–2006, but did not feature in the top forty.