Reuters/Craig Brough
Four years ago in Brazil, Costa Rica took the World Cup by surprise with victories over Uruguay and Italy to win their group and ultimately reach the quarterfinals. It's been a different story for Serbia with eight years passing since they last played in a World Cup. Now these sides will meet Sunday in Samara.
With Brazil the runaway favourites in Group E, Costa Rica, Serbia and Switzerland expect to challenge for second place in the group and advancement into the knockout stage. It's been 20 years, however, since Serbia made it out of the group stage, back when they were part of the Federal Republic of Yugoslavia.
This match-up pits the old against the young, or at least younger. It features a manager's continued trial by fire and a squad that hopes experience will pay off. This contest might be the most pivotal game in the group when all is said and done.
Here's a look at what to keep on eye on: