Costa Rica's success has emerged as one of the most shocking – and profitable - stories of the 2014 World Cup.
Expected to be an afterthought in Group D, Costa Rica followed up its surprising win over Uruguay with an even more surprising one over Italy. Each time, bettors pocketed huge payouts for backing Costa Rica.
Saturday's big underdogs will be looking for big upsets of their own, but can Ghana or Iran compete against two of the top three rated teams in the world?
Group F: Argentina vs. Iran
Argentina is the biggest favorite of this World Cup so far in this game, going off at -900 to beat Iran outright. Iran would pay +1800 on an improbable upset and +900 to force a draw.
Argentina backers might prefer betting the two-way line of Argentina -2.5 (+115) over Iran +2.5 (-140). The total is set at three goals.
Argentina is arguably the best team in this tournament and Iran is arguably the worst, setting the stage for this extremely one-sided betting line. The final score of this game will likely just come down to how much mercy Argentina decides to show.
The team could just go through the motions to pick up the three points in unspectacular fashion, or it could use this game to pad stats and put the offense on display.
Any result other than an Argentina win would be stunning; the margin of victory is what bettors will be trying to cap.
Group G: Germany vs. Ghana
Germany is a -400 favorite on Saturday with Ghana going off at +1000 to win and the draw going off at +525. On the two-way line, Germany is a 1.5-goal favorite. The total is set at three goals.
Germany's power was on display in a dominating 4-0 win over Portugal. The Germans are relentless on the attack, and if Ghana continues to have the defensive lapses that it suffered in its opening game against the USA, Germany will certainly take advantage.
The key for Ghana in this game will be to attack as often as possible, as defending against Germany is too difficult of a task. Ghana controlled most of the game against the United States, but couldn't finish enough of its chances in the 2-1 loss.
With a firm grip on the goal differential tiebreaker, Germany would all but punch its ticket into the knockout round with a win in this game.
Group F: Nigeria vs. Bosnia-Herzegovina
Bosnia-Herzegovina is a -120 favorite over Nigeria. Nigeria +0.5 is a +100 bet, while Nigeria to win outright pays +320 and a draw pays +275. The total for the game is set at 2.5 goals.
Bosnia-Herzegovina played admirably in a 2-1 loss to Argentina, eventually falling victim to a brilliant goal by Lionel Messi that proved to be the game-winner. Going up against a much weaker side in Nigeria on Saturday, Bosnia-Herzegovina will try to earn its first win of the tournament.
Nigeria played Iran to a 0-0 draw in its first game of the World Cup in a game that was maligned as one of the most boring of the tournament so far. The Nigerians are still looking for their first win in World Cup play since 1998.