Costa Rica have been without a doubt the surprise package of the tournament taking seven points and going undefeated in Group D when paired with England, Italy and Uruguay.
It is highly unlikely that anyone correctly predicted the little North American side to have the ability to help knockout Italy the 2006 World Cup Champions or England whom are one of the best national teams in the world but just have not found their form for many of the last years.
Uruguay also fell victim to the Costa Rican attack and failed to capitalize on their group stage survival with their exit to Colombia yesterday.
Costa Rica will have to go into their match with Greece, knowing that the European nation will look to contain the North American side's offense and look to catch them on the break.
Greece have not had a strong offensive showing this tournament, nor do they typically ever in major competitions, and they will look to their strength of containment and breakout in hopes of advancing to the quarterfinals for the first time in their national history.
Costa Riva likewise will be looking for their first trip ever beyond the round of 16, and will rest their hopes of the form of both Bryan Ruiz and Joel Campbell for them to earn another impressive result.
There are no injury concerns for Costa Rica but Greece will have two late decisions with Panagiotis Kone and Orestis Karnezis. Both are expected to be replaced in the first team and start from the bench.
Costa Rican Starting XI: Navas: Gamboa, Duarte, Gonzalez, Umana, Diaz; Ruiz, Borges, Tejeda, Bolanos; Campbell.
Greece Starting XI: Glykos: Torosidis, Manolas, Sokratis, Holebas; Maniatis, Kragounis; Salpingidis; Samaris, Christodoulopoulos; Samaras.