[10] In June 2005, Prass moved abroad and joined Portugal's União de Leiria,[11] as compatriot Helton had left for Porto also of the Primeira Liga.
[12] He made his league debut on 11 September 2005 in a 0–0 home draw against Marítimo,[13] and retained first-choice status from that moment onwards.
[16] Rarely missing a match, he helped the Rio de Janeiro side finish as champions and promote immediately, with the best defensive record in the league.
[17] He helped them return to the top tier at the first attempt;[18] he quickly became a fan favorite due to his saves and was eventually named team captain, as he led them to their third Copa do Brasil title in 2015, scoring the last penalty against rivals Santos in a 4–3 shoot-out victory.
[28] On 29 June 2016, aged nearly 38 and having never earned any cap for the full side, Prass was selected by the Brazil national under-23 team for the 2016 Summer Olympics by manager Rogério Micale, as one of three overage players.
[32] In March 2017, coach Émerson Leão said he would be the perfect choice to lecture younger players in the position who made the national team.