By Gabriel Pessoa/beIN SPORTS

The story of the 2019 Copa Libertadores semifinals could not have been written better if we tried.

There are a total of 14 Libertadores trophies between the four remaining clubs in South America’s elite competition. On one side of the bracket, we have an all-Brazilian matchup comprised of Gremio and Flamengo. On the other side, is a rematch of last year’s controversial Libertadores final between Argentine rivals River Plate and Boca Juniors.

No matter how this stage plays out we are guaranteed a spectacular Brazil vs. Argentina final. But let’s not get ahead of ourselves, there is more than enough to get excited about over the next two legs as that final matchup is decided. Here is what you ought to look out for as the ties kick off with this week’s semifinal first legs.

The 2018 Libertadores Final was both one to remember and one to forget. Not just for the heartbroken Boca Juniors fans who were forced to travel to Madrid to watch their club fight for its seventh South American title and come up short, but for soccer fans worldwide. The unfortunate sequence of events that led to the postponement and relocation of the second leg left a lasting stain on CONMEBOL’s reputation.

On the field, all of the frustration that remains from last year’s final will be unleashed over the next two legs by this new-look Boca team.

Manager Gustavo Alfaro will look to get a positive result away from home on Tuesday, but that will be a tall order as history is fully on River's side. The reigning Libertadores champs are undefeated (three wins, two draws) against their rivals across their last five meetings in the competition.

Alfaro will need key players such as Mauro Zarate, Alexis Mac Allister, Jan Hurtado and team captain Carlos Tevez to bring their A-games if they are to snap that streak.

That said, it will likely not be enough. River Plate currently hold a 13-match unbeaten streak in the Libertadores and we wouldn’t expect it to end on Tuesday at El Monumental.