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The 1931 Campeonato de Portugal Final was the final match of the 1930–31 Campeonato de Portugal, the 10th season of the Campeonato de Portugal, the Portuguese football knockout tournament, organized by the Portuguese Football Federation (FPF). The match was played on 28 June 1931 at the Campo do Arnado in Coimbra between Benfica and Porto, and the former won 3–0 to claim its second Campeonato de Portugal. Most important than the result, however, was its historical significance, as this was the very first official competitive match in their historic rivalry; they had already faced each other a few times in the 1910s and 1920s, but only in friendly matches.
Match
Benfica drew first blood in the 37th minute with a goal from Vítor Silva, and then doubled their lead just before half-time thanks to Augusto Dinis. In the second half, Silva scored his second of the night to seal a 3–0 victory.
Benfica and Porto only had to wait a year for their second official match, which took place in Benfica's home stadium of Campo das Amoreiras in the semifinals of the 1931–32 Campeonato de Portugal, and in which Porto was able to achieve its revenge with a 2–1 win.