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During this derby match, Rui Mendes (a supporter of Sporting) died on site after he was hit inside the stadium by a very light thrown by Hugo Inácio (a member of the No Name Boys). The death happened just after the first goal of the match, when Benfica's Mauro Airez scored 9 minutes into the game, during the subsequent celebrations of Benfica fans in the stadium. Despite the incident in the stands, the match continued.
Following the death, Sporting paid for Mendes' funeral, and the Portuguese Football Federation, showing solidarity with Mendes' family, gave them a subsidy of around 1,650 escudos, 10 per cent of the gross revenue from the match between the Portugal and the Ukraine national football teams, which took place on 5 October 1996.
Mendes was 36 years old and father of two children. Inácio was sentenced to four years in prison in 1998. After escaping from prison in 2000, he was captured in 2011. According to witnesses, including a former member of No Name Boys, the fatal injuries resulted from a deliberate action to cause bodily harm to members of Juventude Leonina (supporters of Sporting), who were at the opposite end of the stadium. The Portuguese Football Federation was ordered to pay 235,000 euros, instead of the €150,000 initially planned to the relatives of Mendes.