Paraguay are no strangers to this tournament. They were the losing finalist four years ago against Uruguay and could be headed to the finals again. They face Argentina today (tomorrow Hong Kong time) in one semi-final. The final is on July 4.

Not only are Argentina in the semi-finals, but all four teams are coached by Argentines: Jorge Sampaoli with Chile, Ricardo Gareca with Peru, Ramon Diaz with Paraguay and Gerardo Martino with Argentina.

Here is a quick look at the last four.

Argentina star Lionel Messi is under pressure to finally deliver, the way he has for his club team Barcelona. Two-time World Cup champions Argentina have not won a major title in 22 years, and Messi is expected to change that.

Messi and Argentina were knocked out of their home tournament four years ago in the quarter-finals against Uruguay, and lost the World Cup final 1-0 to Germany a year ago.

Messi has scored only one goal in the tournament, and Argentina have scored only four in four matches.

Paraguay reached the 2011 finals without winning a single match. They had three draws in group play, and two more in the quarter-finals and semi-finals, where they won on penalties.

Paraguay finished last in 2014 World Cup qualifying from South America, but have rebounded under new coach Diaz, who was the most successful manager at Buenos Aires club River Plate before moving to Paraguay.

Paraguay drew 2-2 with Argentina in group play, and 1-1 with Uruguay before ousting Brazil on Saturday.

Chile have never won the title, and this is supposed to be the year with top players - like midfielder Arturo Vidal of Juventus, forward Alexis Sanchez of Arsenal, and goalkeeper Claudio Bravo of Barcelona - lighting up their side.

Peru are the surprise, and they also have a longstanding regional rivalry with Chile. Peru opened with a 2-1 loss to Brazil, but defeated Venezuela 1-0 and then reached the quarter-finals with a scoreless draw against Colombia.