Franco Armani's performance for River Plate is garnering calls for the goalkeeper to net a spot for Argentina in this summer's World Cup. Marcelo Endelli/Getty Images

The Copa Libertadores is exactly halfway through the group phase. A total of 32 teams are divided into eight groups, and all of them have now played three matches. So what conclusions can be drawn at this early, but strategic stage?

Customary balance prevails

The price that Europe's Champions League pays for quality is predictability. The same clubs are back in contention for the title year after year, often making their way to the knockout stages with a series of easy wins. These days the South American club game cannot hope to compete in terms of quality -- their best players are continually sold abroad. But that does mean that things are much more unpredictable back at home. Even the biggest teams are in a continual state of flux, since their success puts players in the shop window.

There are two ways in which one statistic from the 2018 Libertadores is so striking. Only one of the 32 clubs has a 100 percent record. Twelve might be unbeaten, but only one has registered three consecutive victories in this tournament.

And that one is not a traditional giant from Brazil or Argentina, or even one of the 16 former champions in the field. It is Libertad of Paraguay, a relatively modest club, not even one of the country's traditional big two. Libertad have become regular Libertadores competitors in the present century, but they have never made it to a final. Neither have Cerro Porteno, their much bigger neighbours. But they, too have made an impressive start, with two wins followed by a draw against reigning champions Gremio -- the only match the Paraguayan sides have not won in this year's competition.

Extra spice is added by the battle for World Cup placement

Of the South American national teams going to the World Cup, there are few home-based players in contention for a place in the squad for Russia. But there are some -- and one of the extra layers in the Libertadores this year is whether the competition can serve as a platform for World Cup ambitions.

It is certainly helping the cause of River Plate goalkeeper Franco Armani. He made his name in Colombia, especially in a highly successful five year spell with Medellin giants Atletico Nacional. There was even talk of Colombia naturalising him and using him in the World Cup. But at the start of the year he moved back to his native Argentina to join River Plate. He had half an eye on crashing his way into the Argentine national team, where the goalkeeping position is complicated by the fact that first choice Sergio Romero spends his time on the Manchester United bench.

Everything is going to plan for Armani so far. He is in fine form -- and his national team prospects are perhaps aided by playing behind a suspect defence. The River Plate fans are calling for his inclusion by Argentina -- in the starting lineup, not just the squad -- and the local media have added their weight.

The calls will be louder still after Thursday night, when River Plate spent the second half hanging on for a 1-0 win away to Emelec of Ecuador.

Breakout young stars on display

The Libertadores can be a wonderful place to talent spot youngsters on the way up. One who certainly fits into that category this year is Lautaro Martinez, centre forward with Racing of Argentina. With a rich penalty area repertoire and touches of undoubted class, he would seem set for a bright future. Four goals so far -- all against Brazilian opposition -- have made his case for inclusion in the Argentina World Cup squad, as well.

One who will not be going to the World Cup is Angelo Araos. His country, Chile, did not qualify, and now need to think about the future as their golden generation heads for the exit. Araos looks to be the kind of player with a huge role to play in the rebuilding process. A support striker with Universidad de Chile, his coach Angel Guillermo Hoyos was one of the first to work with Lionel Messi at Barcelona. Hoyos, then, can speak with a certain credibility, and he says that Aras reminds him of Enzo Francescoli, the great Uruguayan. The young Chilean's ability to receive the ball back to goal and roll past his opponent -- best seen in the winning goal away to Vasco da Gama -- bears out the comparison.

Then there is Real Madrid-bound 17 year old Vinicius Junior of Flamengo, who came off the bench away to Emelec and turned almost certain defeat into vital victory with two goals of sublime talent. A day later Rodrygo of Santos, an even younger Brazilian, scored a crucial goal against Nacional of Uruguay.

Whatever happens to these players in the years to come, they will never forget the boost that the 2018 Copa Libertadores gave to their careers.