RIO DE JANEIRO -- The Gods of Football gifted us two bona fide rivalries in the Copa America semifinals.

Headlining is Brazil vs. Argentina (Tuesday, 8:30 p.m. ET; ESPN+), the "SuperClasico de las Americas" and, in terms of pedigree, one of the few international matchups that lives up to the hype, usually in terms of quality and almost always in terms of incident.

But the "Pacific derby" -- Chile vs. Peru (Wednesday, 8:30 p.m. ET; ESPN+) -- is an intriguing understudy, rich in a rivalry that often transcends football and not just over the paternity of the "Pisco Sour."

Indeed, one of the twists is that no matter what happens, Chile and Peru are playing with house money, whereas Brazil and Argentina are pretty much assured inquests, pulling of hair and gnashing of teeth if they stumble at this hurdle.

Let's start with the big one. Brazil and Argentina have faced off for more than 100 years and reached 12 World Cup finals between them, winning seven. They have produced three unquestioned GOAT candidates -- Pele, Diego Maradona and Lionel Messi -- spawned oodles of sociological treaties about the importance of futbol/futebol to their national psyches and generally have been the yin to each other's yang.

In 105 previous meetings, there have been 41 wins for Brazil, with 38 for Argentina and 26 draws. If you discount friendlies, then Argentina are ahead, 18 to 17.

Not that too many encounters have been very friendly; from pitch invasions (1925), to Brazil walking off (1937), to Argentina walking off and Brazil scoring the winning penalty into an empty goal (1939), to police invading the pitch to stop the teams fighting (1946), to the "Battle of Rosario" (1978), to Maradona's horror tackle and red card at the World Cup (1982), to Maradona's genius right-footed pass for Claudio Caniggia and subsequent "holy water" controversy (1990), to five players getting sent off in the Copa America (1991) to Tulio's "hand of the devil" goal (1995), this rivalry has had plenty of controversy.

The last time they squared off in the Copa America was back in the 2007 final. Twelve years later, two of the protagonists are still around: Dani Alves, who came on and scored in a 3-0 Brazil win, and Messi, who had just turned 20 at the time.

Some reckon Tuesday's clash will be different, since many players are teammates in their day jobs. Messi is at Barcelona with Philippe Coutinho and Arthur. Gabriel Jesus lines up with Nicolas Otamendi and Sergio Aguero at Manchester City. Leandro Paredes and Angel Di Maria share a dressing room with Marquinhos; and Thiago Silva and Dani Alves at Paris Saint-Germain. Paulo Dybala and Alex Sandro break bread at Juventus.

Yeah, right. And the Easter Bunny loves hiding those eggs ...

The fact is, globalization, commercialization and, yeah, cold hard cash might have turned these guys into colleagues and maybe even friends, but this is different. This is international football. This is playing for your country.

And the usual pressure and stakes are ratcheted up further by circumstances. Brazil are still scarred by the aftereffects of the Mineirazo, the 7-1 World Cup semifinal defeat against Germany in 2014 that induced a one-way ticket to "The Twilight Zone." (Yes, they return to the scene of the crime for this game.)

It will take time to expiate, and another major trophy might accelerate the process, but the 2015 Copa America went off the rails when Neymar was banned and ended with a penalty shootout exit against Paraguay in the quarterfinals. A year later, Brazil failed to get out of their Copa America Centenario group.

Hopes were high for a fresh start at World Cup in Russia and plenty jumped on the Tite bandwagon, only for it to be derailed by Roberto Martinez and Belgium in the last eight. It is 12 years and counting since the Selecao's last major tournament win, not including a pair of Confederations Cup triumphs in 2009 and 2013.

There is still plenty of faith in Tite, and the major mitigating factor of Neymar's absence this time around weighs heavily in a rational assessment of the tournament. But this is Brazil and this is home soil, which means reason will quickly go through the power shredder should things go awry against the old enemy.

For Argentina, the pressure is myriad. First, there is the Messi issue. His detractors never miss the opportunity to point out his lack of trophies in an Albiceleste shirt, just as his supporters point to his four finals -- three in the Copa America, one in the World Cup -- and the fact that his side were twice beaten on penalties and once in extra time.

Knocking this eternal -- and, frankly, puerile -- debate on the head once and for all would be nice, particularly because, having turned 32 last week, Messi is not getting any younger. The idea that Argentina have failed to grab any silverware in nine attempts with one of the greatest players in history is an indictment of one of the game's traditional powers.

More broadly, there are other stains to wipe away, starting with the memory of Russia. It was not just the shambles at the tournament itself, where Argentina scraped through the group stage only to be beaten by France, but the embarrassingly chaotic qualifying campaign, which featured three managers and last-ditch turnarounds.

Moreover, there are the continuing difficulties of the Argentine FA (which, lest we forget, led Messi to announce his international retirement in 2016) and the fact that manager Lionel Scaloni has an interim contract that expires the moment Argentina are eliminated from this tournament.

Scaloni was charged with limiting "Messi dependency" and putting together a rational framework. After fits and starts in the group stage -- marked by copious changes in system and personnel -- he seems to have found some sort of balance in a 4-3-1-2 with Rodrigo De Paul in midfield, Messi in the hole and Lautaro Martinez alongside Aguero up front. It did the job against Venezuela, but it feels fragile enough that it could be blown away should old insecurities crawl back in.

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Meanwhile, Chile and Peru have effectively already won their respective Copa Americas. Chile are two-time defending champions dreaming of a three-peat, but the landscape is different and not just because they are in Brazil's house (they hosted in 2015 and the Centenario was on "neutral" territory in the United States).

Eight of the starting XI that knocked out Colombia in the quarterfinal are in their thirties, and another, Edu Vargas, turns 30 in November. The high-energy, flat-out, run-and-gun style that helped deliver those two titles is no longer an option, not for 90 minutes anyway.

As such, Chile must pick their spots. And with Alexis Sanchez coming off a nightmare campaign at club level -- he has scored as many goals (two) in four games at this tournament as he did in 27 appearances for Manchester United last season -- few expected them to get this far.

But Reinaldo Rueda's crew will start as favourites on Wednesday, mainly because Peru were not just unfancied before a ball was kicked, but due to the fact they have been lackluster in reaching the semifinals. Their only win was a comeback victory over Bolivia; they were hammered 5-0 by Brazil, and in the previous round, they survived three disallowed goals and failed to get a shot on target before ousting Uruguay on penalties.

"From a mental perspective, we're in good shape," Peru coach Ricardo Gareca said after that win. "Of course, when it comes to the footballing side, there's room for improvement."

Maybe so, but when margins are slim, every inch is contested and penalty kicks and intestinal fortitude often come into play; that "mental strength" to which he alluded could be key. It applies whether you are playing nearly pressure-free, such as Chile and Peru, or have the weight of the world on your shoulders, like Brazil and Argentina.