The cup was an international quadrangular , comprising friendly matches between Estudiantes , Gimnasia , Club Nacional de Football and Club AtlÃ tico PeÃ arol , the latter being the two main football clubs from Uruguay . The cup was an international tournament , comprising friendly matches between Estudiantes , Gimnasia , Club Nacional de Football and Club AtlÃ tico PeÃ arol , the latter being the two main football clubs from Uruguay .