A rivalry that has lasted for over a century, the Grenal derby has never disappointed in providing fireworks, both in terms of the sparkling football and off-ball drama.
Grêmio and Internacional have contested some feisty encounters over the years and both sides have never quite been able to dominate this fixture, with Inter winning just 23 more of their 424 encounters that have been played in total.
So having read the story behind one of Brazil's biggest derbies, here are five of the greatest clashes in Grenal's long and proud history.
What looked set to be a momentous occasion in Internacional's history ended up being a day to forget for the newly created club.
It was the Poppe brothers, founders of Colorado, who decided for their very first game to challenge their rivals Grêmio. The older team agreed, but offered to field a reserve team for the match, which was quickly refused - a decision that backfired badly on Clube do Pavo.
In front of a passionate crowd of 2,000, Imortal Tricolor ran riot, tearing their opponents to pieces in a comprehensive 10-0 thrashing. German forward Edgar Booth would end up scoring five goals himself for the home side, while the Grêmio goalkeeper Kallfelz ended up abandoning his goal during the game to have a chat with supporters instead.
A century later, the result remains the biggest victory in the derby's history.
O "Gre-Nal do Século", como é conhecido, foi um dos maiores jogos da história do Beira-Rio, pois ficou marcado pela grande virada colorada em cima de seu maior rival, garantindo a vaga na final de mais um Campeonato Brasileiro.
This remains the encounter that defines the Grenal rivalry - so much so, that it's referred to as the 'Grenal of the Century'.
The first-leg of this Campeonato Brasileiro Série A championship semi-final had ended goalless, and lined up at the Estádio Beira-Rio knowing fully that both a place in the final and qualification for the following season's Copa Libertadores were the prize for the winner.
On a scorching hot day, the away side started the game well, and soon took the lead through Marcus Vinicius. With Colorado then having their right-back Casemiro sent off just before half-time, the stage looked set for Grêmio to claim a huge away victory.
But as the game went on, the hosts worked their way back into the match. And they got their reward, as top-scorer Nílson equalised to draw his team level. With momentum truly on their side, Inter pushed hard for a winner.
When their midfielder Maurício shot from distance, the ball looked to be heading wide for a goal-kick. But up popped Nílson again, who diverted it into the back of the net, to complete the turnaround. Despite defending with ten men, Clube do Pavo held on for the famous win, which is regarded as one of the best in the derby's history.
To Grêmio fans, this is widely remembered as the game a young teenager named Ronaldinho burst onto the scene.
With both teams winning a game each, it came down to the third and final game in the series to decide the winner of the 1999 Campeonato Gaúcho championship. And knowing how dangerous Imortal Tricolor's young star could be, Internacional coach Paulo Autuori instructed the hard-as-nails World-Cup winning captain Dunga to man-mark the prodigy throughout the game.
As Autuori found out, that move would not stop the future Barcelona star at all. Dunga was given a torrid time by Ronaldinho, who put on a dazzling show of tricks, including his signature elástico move to embarrass the veteran midfielder.
And it was his brilliant individual goal, that included a one-two and nutmeg in the build-up, that gave Grêmio the crucial win that won them the championship. While the game isn't remembered as a classic, the match-winning display of Ronaldinho remains a sheer delight to watch to this day.
Both sides met each other again in another Campeonato Gaúcho championship final, and with the first-leg ending goalless, it would all come down to the all-important return fixture.
In a noisy Estádio Beira-Rio, neither team could find a way to score in the first-half. But it was the hosts who drew first blood, as a goal from Fernandão put Internacional in front.
Yet Grêmio were determined to fight back, and pressed hard for an equaliser. With the game heading into the closing stages, substitute Pedro Júnior found the net for the visitors, setting off wild celebrations amongst the travelling 6,000 Gremistas.
And the late equaliser ended up being the deciding factor, as Imortal Tricolor ended up lifting the championship on away-goals. It ended Internacional's hopes of winning a fifth consecutive state title too, making this a highly memorable game for every Grêmio supporter.
This isn't a game to remember for the football - rather it's the off-ball antics that will catch your eye.
It was always going to be a tasty affair between the two rivals, who were drawn in the same Copa Libertadores group, and had never played each other before in the competition. And boy, did the tension spill over in spectacular fashion.
With the game itself heading for a goalless draw, Internacional player Moisés and Grêmio's Pepe squared up, which was quickly spotted by the referee. But just as cooler heads seemed to have prevailed, an exchange of words kick-started the fighting again, with substitutes and staff getting involved in what became a mass brawl.
It lasted for a staggering ten minutes and when the dust settled, both sides ended with eight players-a-side as three from each team were sent-off by the officials, as well as a substitute each.
This would be one of the last games to be played in Brazil before football was suspended due to the coronavirus pandemic. It's fair to say the two teams finished with a bang, quite literally.
Grêmio vs Internacional: The Most Fiery and Competitive Game in Brazil
As many of you will know, there's nothing quite like a Brazilian football rivalry. Few places share the same level of fiery fan atmospheres, feisty tackles, and the passionate goal celebrations from any of the players fortunate to score.
If you ever get a chance to travel to the southern city of Porto Alegre, you'll find that their citizens are very much divided in their football loyalties. They'll either be wearing the blue of Grêmio, or the red of Internacional.
Indeed, some Brazilian football observers describe this fixture to be the biggest and most special of all the games played in Brazil. There's a cultural reason to back up their argument.
Both teams play in the Rio Grande do Sul state, which is heavily influenced by the gaucho culture. These brave fighters often saw themselves to be separate from other Brazilian states, and felt the need to take on the rest of the country and defeat them as a source of pride.
Internacional fans are always up for the Grenal clash | Lucas Uebel/Getty Images
And it's that fighting spirit that has shaped the century-long opposing hatred between two of the region's biggest clubs, which still remains as passionate and feisty since the origins of the game itself.
Their rivalry stems from a class conflict - that goes back just over a century ago, not long after Grêmio was founded in 1903 by a group of Porto Alegre locals who were part of the city's German community, led by entrepreneur Cândido Dias.
Six years later, the team drew the attention of the Italian migrants Henrique, Jose and Luis Poppe. To them, the club seemed to be exclusive in favouring the German community of the city over other societal groups.
As a result, they went off to form Internacional, with the name of the team a pointed reference to their now city-rivals. Their creation was intended to be a team for the people, regardless of their background - as referenced by their long-standing nickname Clube do Povo.
Despite their lofty ambitions, it was a bumpy start for the newcomers. The 1909 encounter is considered the first derby between the two sides, and ended up being a 10-0 win for Imortal Tricolor. They were so dominant that their goalkeeper allegedly ended up coming off the pitch during the game to chat to supporters instead.
But the game has become a lot more competitive since that very first meeting. Of the 424 encounters that have been played in total, Internacional have won 156 of them, while their rivals are not far behind on a total of 133 victories.
Both sides are clearly the most successful in the Rio Grande do Sul state - of the 89 Campeonato Gaúcho state league titles, they've collectively won a whopping 83 of them - with Inter slightly ahead of their rivals, having won 45 state championships to Grêmio's 38.
Meanwhile, it's hard to separate both teams in finding who's the more successful club on both a national and continental level. Grêmio have lifted the prestigious Copa Libertadores three times, one more than Colorado's total. Yet they have fewer Brazilian Serie A championships compared to their younger counterparts.
This fiery clash has additionally seen some of the world's best players elevate the game further with some breathtaking displays fit for such an important occasion.
Probably the most famous person to have played for Imortal Tricolor is Brazilian legend Ronaldinho, but even the likes of Emerson, Juventus winger Douglas Costa and Barcelona midfielder Arthur have also come through their ranks and played in this special match too.
On the other hand, Internacional have also had their fair share of stars play in their red and white colours. They include the Brazilian midfield star Falcão, Elías Figueroa and current Liverpool stopper Alisson - all of whom have represented the club.
Internacional goalkeeper Alisson in action against Grêmio | Lucas Uebel/Getty Images
And both have produced some fantastic teams in their history. The 'Rolo Compressor' side Colorado put out in the 1940s were a joy to watch, dominating the lion-share of derbies during the period.
Meanwhile, the Grêmio team of the 1990s were not a bad side to watch, with multiple trophy successes under the management of future Chelsea and Portugal boss Luiz Felipe Scolari.
Even now, games between the two sides never disappoint. The 2020 fixture instantly went viral on social media, with a ridiculous number of eight red cards dished out, as a mass brawl took place between players and staff on both sides.
Even today, it's still a fiery encounter for both sides | Lucas Uebel/Getty Images
This only suggests that there's more drama and entertainment to come from this fixture in the years to come, as the pair continue to battle for the title of being Porto Alegre's best team. And given that there's many rivalries out there that have lost its competitive nature, it's refreshing to see two teams go at it - with both having an equal chance of winning the fixture.
For that and more, there really is nothing out there like the Grenal derby.
Ricardo Chaves / Agencia RBS
A FULL OUT BRAWL HAS BROKEN LOOSE IN THE GREMIO-INTERNACIONAL GAME! 
