Gre-Nal stands for every match opposing the two main forces of southern Brazilian soccer, "Grêmio" versus "Internacional", two highly successful football clubs based in the same city – Porto Alegre, the capital of the southern state of Rio Grande do Sul. Grêmio was Intercontinental Champion, two times winner of the Copa Libertadores (South American Champions' League), has won 2 brazilian championships, 4 brazilian cups and 34 state cups. Internacional (also called "colorado" and "Inter") has won 3 brazilian championships, one brazilian cup and 37 state cups.

It is perhaps the fiercest and one of the most mystic football rivalries in Brazil, every encounter being accompanied by extremely high levels of emotion on either side. A Gre-Nal is in general a very competitive (and at times violent) match where some of the greatest Brazilian players (e.g. Ronaldinho, Falcão, Taffarel, Dunga, Emerson, Éder, Everaldo, etc.) and coaches (e.g. Luiz Felipe Scolari and Tele Santana) have had their claim to fame. Every Gre-Nal is not only played, but almost “fought” since winning or losing a Gre-Nal has a particularly emotional meaning in Southern Brazil. The rivalry of Gre-Nal is a phenomenon that goes beyond the football sphere. Within the city of Porto Alegre and within the state of Rio Grande do Sul, everyone “belongs” very strongly to one of the two sides, according to very complex familial, cultural and socio-demographic factors. For instance, Grêmio was founded in 1903 by German immigrants who banned the entrance of black players, while Inter was founded by Italian, Portuguese and Spanish immigrants, and was the first of both clubs to use Blacks and mixed players. However, since the 50es, the situation has actually changed, and several black players such as Ronaldinho and Everaldo went on to become idols of Grêmio. As another example of this complexity, as Inter was highly successful in the seventies, many people who were children and teenagers in the seventies went on to become supporters of Inter, whereas the frequent successes of Grêmio in the 80es and 90es inverted the situation.

Despite the strong rivalries between supporters, hooliganism is non-existent in a Gre-Nal and outbursts of physical violence between groups of supporters are rare. Between matches, the rivalry is usually lived as an opportunity for good-humoured discussions between opposing sides, creating a special, colorful aspect of everyday life in the state of Rio Grande do Sul.

As of june 2006, the clubs played against each other an impressive number of 365 matches: 136 victories for Inter, 116 for Grêmio and 113 draws. The biggest win for Grêmio was 10X0 in 1909 (the very first Gre-Nal) and the biggest win of Inter was 7X0 in 1948.

Football (soccer) rivalries | Football in Brazil