Marlos Moreno shines as Atletico Nacional impress in Copa Libertadores
Portuguese-speaking Brazil takes up about about half of South America. Of the rest, the Spanish speaking half, the two nations with the largest population are Argentina and Colombia -- who, in recent times, have developed a fascinating football rivalry.
There is something of a father and son feeling in the dispute. When Colombia launched its professional league in the late 1940's, Argentina was well established as one of the giants in the game. As chance would have it, Argentina's players decided to go on strike at that very moment. With the big stars in dispute with their clubs, Colombia's new league, the China of its day, took advantage by taking them north. Argentina helped build Colombian football -- with its players, coaches and even its fan culture. So when, in 1993, Colombia inflicted Argentina's first-ever home defeat in World Cup qualification -- by the extraordinary margin of 5-0 -- some saw it as a case of patricide.
Despite that scoreline from 23 years ago, Argentine football remains a leading power while Colombia has more potential than achievement. In club terms, for example, Argentine teams have won the Copa Libertadores on 24 occasions, while Colombia can point to just two triumphs.
Even so, the two clashes between clubs from these nations were among the most eagerly awaited matches in the second week of this year's Libertadores campaign. Colombia came out on top after Atletico Nacional of Medellin won 2-0 away at Huracan, while Deportivo Cali drew 0-0 at home to Boca Juniors.
Atletico Nacional's victory was notable for the unleashing of a player who came through strongly in domestic football towards the end of last year. Marlos Moreno, 19, was the revelation of the Colombian championship, cutting in from the left with pace, balance and skill. For the club's Libertadores debut, coach Reinaldo Rueda used him in a slightly different role: more centrally, operating off the improvised striker Victor Ibarbo. Moreno responded wonderfully well.
He opened the scoring with a blistering shot, all natural talent and pure conviction. And he set up the second goal, too, slipping a pass behind the defensive line for Orlando Berrio to score. If the first goal showed off his skill, the second highlighted his maturity -- the most astonishing feature of his display was the soundness of his decision making -- when to pass, when to dribble and when to shoot.
It was a sensational performance which tipped the balance and effectively won the game, though in this case the victory was not a complete surprise, even coming away from home. Huracan would seem to be the weakest of the six Argentine representatives in this year's competition, while reigning domestic champions Atletico Nacional are the best Colombia has to offer.
For this reason, the Deportivo Cali vs. Boca Juniors game was such a big draw. It held the promise of a well-balanced encounter between two interesting sides. Boca were double winners in Argentina last year and have more pedigree, but Cali could count on home advantage -- and a team full of promising youngsters.
They may not quite be in the Marlos Moreno class, but the Cali front duo of Harold Preciado and Rafael Santos Borre are still mighty impressive. Preciado is rangy and powerful, as well as technically gifted, a natural centre forward. Santos Borre is mobile and quick thinking -- a born second striker. The pair are good individually and can be better together. They had to live off scraps against Boca, but they gave the Argentine defence an interesting night. Preciado came closest to a goal when his shot from the right edge of the area thudded back off the near post. And Santos Borre also went close, taking advantage of a Preciado dummy to turn right and shoot just wide.
In a niggly game, with nine yellow cards shown, Boca had more of the possession. It was a good night, too, for some of their youngsters.
Defensive midfielder Adrian Cubas is a little player with a big personality, and his lanky Uruguayan colleague Rodrigo Bentancur has a touch of a left footed Lucho Gonzalez about him, with his elegance and versatility. He blocked the forward runs of Cali's attacking right-back Helibelton Palacios, and also played some intelligent diagonal passes.
There were times when Boca seemed about to take control, Fernando Gago knitting the side together and supplying Carlos Tevez in the space between the lines of the Colombian side. But it was more smoke than fire -- and it was the young strike duo at the other end who came closest to breaking the deadlock.
The sides meet again in the final group game in almost two months' time and it could well be a decisive confrontation. They are in a tricky group -- with Racing of Argentina, a team with plenty of attacking quality, and Bolivar of Bolivia, where no one will relish the trip to the extreme altitude of La Paz.
This latest clash between Argentina and Colombia, then, could have another fascinating chapter written in Buenos Aires on April 20.
Tim is an English journalist who has been based in Brazil for over 20 years. He is the South American football correspondent for the BBC Sport website.