haʊˈɛvɚ, mˈæɾɪəs wʌz æt ðə sˈɛntɚɹ əvə dʒuːdˈɪʃəl kˈɑːntɹəvˌɜːsi ðæt ɪɹˈʌptᵻd ɪn pˌoːɹtʃəɡˈiːz fˈʊtbɔːl, nˈoʊn æz kˈɑːsoʊ mˈæɾɪəs mˈæɾɪəs ɐfˈɛɹ, ˈæftɚɹ ɐ səpˈoʊzɪdli ɪlˈiːɡəl ɹˌɛdʒɪstɹˈeɪʃən baɪ ðə bɑːɹsˈiːloʊz klˈʌb.
However, Mateus was at the centre of a judicial controversy that erupted in Portuguese football, known as Caso Mateus (Mateus Affair), after a supposedly illegal registration by the Barcelos club.