After two seasons at the Camp Nou, Couto left "Barça" and joined Rome's S.S. Lazio in late June 1998 as teammate Iván de la Peña. He appeared in 22 matches in his first year to help his team to the second place in the league, and featured one minute in the final of the last Cup Winners' Cup, in a 2–1 win against RCD Mallorca at the Villa Park in Birmingham.