Those players who picked up a yellow card during the group stage will have to be cautious during the Round of 16 games.

The most heart-breaking stage of the FIFA World Cup will begin tomorrow, and given that all footballers will be as intense as ever to try and lift their teams to glory, some of them have to be cautious enough to keep themselves away from yellow or red cards.

Those players who were booked during the group stage are NOT in the clear, since FIFA erases all yellow cards after the Quarter final stage. This measure was taken to have all key players available, with a red card being the only way in which a top-caliber player could miss the FIFA World Cup final.

In the next few days, all eyes will be on Cristiano Ronaldo, Neymar, Lionel Messi and many others, but these three players in particular have to be aware that one yellow card could make them miss the next game of the tournament.

Here's the list of all those players who are still in the title race but have to be cautious to avoid being banned.

Argentina: Ever Banega, Gabriel Mercado, Javier Mascherano, Lionel Messi, Marcos Acuña, Nicolás Otamendi.

Belgium: Jan Vertonghen, Kevin De Bruyne, Leander Dendocker, Thomas Meunier, Youri Tielemans.

Brazil: Casemiro, Neymar, Philippe Coutinho.

Colombia: James Rodríguez, Johan Mojíca, Wilmar Barrios.

Croatia: Ante Rebic, Ivan Rakitic, Marcelo Brozovic, Mario Mandzukic, Marko Pjaca, Sime Vrsaljko, Tin Jedvaj, Vedran Corluka.

Denmark: Mathias Jorgensen, Pione Sisto, Thomas Delaney.

England: Kyle Walker, Ruben Loftus-Cheek.

France: Blaise Matuidi, Corentin Tolisso, Paul Pogba.

Japan: Eiji Kawashima, Makoto Hasebe, Takashi Inui, Tomoaki Makino.

Mexico: Héctor Herrera, Jesús Gallardo, Miguel Layún. (Héctor Moreno is banned for Mexico's game vs Brazil)

Portugal: Adrien Silva, Bruno Fernandes, Cedric, Cristiano Ronaldo, Raphael Guerreiro, Ricardo Quaresma.

Russia: Aleksandr Golovin, Fedor Smolov, Iuri Gazinsky.

Spain: Sergio Busquets

Sweden: Albin Ekdal, Mikael Lustig, Viktor Claesson. (Sebastian Larsson is banned for Sweden's game vs Switzerland)

Switzerland: Denis Zakaria, Valon Behrami, Xherdan Shaqiri. (Stefan Lichtsteiner and Fabian Schär are banned for Switzerland's game vs Sweden).

Uruguay: Rodrigo Bentancur.