After started playing professionally for modest Portuguese teams (he had a stint with Sporting CP, but never moved past their reserves), he signed in January 2006 with Gil Vicente F.C.
[3][4] After an uneventful season with Gil Vicente in the second division, greatly delayed by the legal consequences,[5] Mateus joined Boavista F.C.
In the same season, he played six games and scored four goals as they reached the semi-finals of the Taça de Portugal, including one in each leg of a 5–2 aggregate elimination by F.C.
[8] Mateus continued to be play frequently for the better part of the following years, notably netting nine goals in 24 matches in the 2011–12 season.
[21] He scored on his debut on 29 April in a 5–1 win over Mauritius,[22] and again the next day in a 3–1 victory against the hosts,[23] as his team came runners-up to Zambia.
Later in 2006, Mateus was called up to that year's FIFA World Cup, playing all three group stage matches including the entire 1–0 loss against Portugal.
On 8 October 2011, Mateus scored as Angola won 2–0 away to Guinea-Bissau to pip Uganda to a spot at the 2012 Africa Cup of Nations.
[25] At the tournament in Gabon and Equatorial Guinea, he scored the first goal of their opening 2–1 defeat of Burkina Faso, but Lito Vidigal's team were eliminated from the group.
Mateus scored four times in qualification for the 2019 Africa Cup of Nations, coming in braces in wins over Mauritania (4–1) and Burkina Faso (2–1).