With two fewer players, Belenenses was soon trailing. Benfica scored all goals in the 7-0 win in the first half.
The referee called the match off just after the start of the second half. Only seven players took the field for Belenenses, which soon lost another player when one dropped to the turf, leaving them with only six.
The laws of soccer allow for games to be played as long as each team has seven players, including a goalkeeper.
Club president Rui Pedro Soares said that despite having a decimated squad his club did not ask for the game to be postponed.
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