Each making their first-ever appearances in the World Cup round of 16, one of Costa Rica or Greece is guaranteed to go one step further in booking a maiden World Cup quarter-final on Sunday.
It will be a terrific achievement for either outfit, and there will be no love lost between the two debutants as they look to advance further in Brazil, coming through their group fights in near-opposite fashions.
Group D winners Costa Rica are aiming to maintain their unbeaten streak this weekend, with all viewing information detailed ahead, along with form guide and a prediction of how things will unfold at the Arena Pernambuco.
Date: Sunday, June 29
Time: 9 p.m. BST/4 p.m. ET
TV Info: ITV (UK), ESPN (U.S.)
It's no secret that Costa Rica's World Cup surge has been a surprise for all to witness, and Jorge Luis Pinto may even be shocked at their success himself given the team's form coming into the tournament.
The Central Americans won just one of their six friendly outings in preparation for the tournament, but it may well be the case that they've simply chosen to learn from their mistakes in the correct manner.
Now, Pinto's men are unbeaten in their last four, and Squawka illustrates that defensive understanding may be at the root of their success:
Greece, meanwhile, have a similar recent winning form to their upcoming opponents, claiming victory twice in their last eight games but managing to score a goal in just three of those fixtures.
It's not an encouraging sign for the European minnows, and Sky Sports' South American correspondent Paulo Freitas agrees that their chances aren't strong heading into Sunday's clash:
Fernando Santos' side had to wait until their final group game against the Ivory Coast to score their first goals of the World Cup, while Costa Rica have failed to net just once in their last six games.
Despite the reputations these two sides may have held coming into the competition, the Costa Ricans now sit as considerable favourites to book a quarter-final place after this fixture.
As discussed, their defence has been rigid so far in Brazil, and with Greece struggling to find the goal of late, it's difficult to see where an attack led by Georgios Samaras will find its inspiration.
Pinto was able to rest a few of his key players for the 0-0 draw against England last time out, and that restoration will also help La Sele in taking advantage of a less-than-fresh Greek line-up.
Prediction: Costa Rica 2-0 Greece