Coimbra-based Academica, nicknamed "the students", had won the Cup only once, in its very first edition in 1939. The defeat dealt a severe blow to Sporting and coach Ricardo Sa Pinto who end the season trophy-less.
Marinho, the shortest player on the pitch, wrote his name in Academica's history books when he sneaked behind Sporting's defence and headed home after only four minutes.
Sporting, recognised as one of Portugal's "big three" clubs together with Benfica and Porto, were slow and often clumsy in their build-up play and succumbed to Academica's focused and well-organised tactics.
The Lisbon club missed their best chance to equalise in the second half when Dutch striker Ricky van Wolfswinkel failed to beat keeper Ricardo when through on goal.
But Academica, who had to battle hard to avoid relegation this season, fought on and ended their season in glory thanks to some resolute defending.
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