Two of the Cup's best teams collide
What's on the line
The war of words has already started between these two perennial World Cup favorites, who have a combined five titles. With some bad blood remaining from a quarterfinal matchup in the Cup four years ago, the 2010 version is sure to be an interesting one.
Style and tactics
Germany, at its best, has been by far the most impressive team. Though the central defense remains suspect, Mesut Ozil and Thomas Mueller spearhead the most potent attack in South Africa. Ozil, in particular, has been a revelation this summer with his midfield play leading the way. Argentina provides the most potent attack the Germans have yet faced, though, so Ozil and Co. must try to get on the board early, as they did against England.
Meanwhile, Argentina reached the quarterfinals with a perfect record in South Africa. And that came without the outstanding performances everyone expected Messi to provide. Messi has been solid but not the whirlwind force he has been at Barcelona. If he can find that form, Argentina will be virtually unstoppable. The squad has plenty of other attacking options, though, with Carlos Tevez and Gonzalo Higuain both looking strong.
Players to watch
Javier Mascherano, Argentina. In this game, Mascherano has the unenviable task of marking Ozil -- and this is a matchup that could go a long way in deciding the game. Mascherano, a standout for Liverpool and for his national team, has had a strong World Cup so far and rarely makes mistakes on the world stage. Ozil, though, provides by far the toughest challenge he's faced in South Africa, as the German's free-running style likely will leave Mascherano on his back foot.
Lionel Messi, Argentina. Though placing Messi as "one to watch" seems a bit of a waste, as everyone watches him anyway, it is more relevant than ever against Germany. With pundit after pundit claiming that Ozil is "outplaying" FIFA's World Player and with the ever-growing pressure to score, Messi could silence his critics with a significant goal against Germany. Also, many of Argentina's attacking moments against Mexico came after defensive errors from El Tri. Germany will not give up chances so easily, so Messi will need to be on his game.
Thomas Mueller, Germany. Ozil, obviously, is a candidate to be man of the match. But one of his partners in crime -- and perhaps the man he works best with -- is the 20-year-old striker who has impressed despite his young age this summer. A favorite to win this tournament's Young Player award, Mueller has three goals and three assists in four games (including a brace against England in the Round of 16). Against Argentina's suspect defense, he could have another breakout game.
Manuel Neuer, Germany. Neuer has kept his cool so far, but the attack he will face in Argentina is miles ahead of anything he's seen in earlier games. And if the match goes to penalty kicks, will he be able to maintain his steady calm?
What we can expect
One of the most entertaining games of the tournament. This matchup will have the quality of a final, and whichever team comes out victorious will have to be considered a favorite to go all the way. Both Argentina and Germany have lived by their offenses this year, meaning this game should include plenty of open chances. And with players such as Ozil and Messi on the field, there should be no shortage of "Can you believe that?" moments.
There's plenty of bad blood in this matchup, following the two teams' quarterfinal matchup in 2006. The Germans are taking offense with Argentina's behavior in that game, which saw the Argentine players storm the field after being eliminated on penalty kicks. Punches were thrown, and even team officials came off the bench to get involved.
The German players began their war of words against the Argentines almost a week before the game began, when Bastian Schweinsteiger accused the squad of a "lack of respect" based on their matches in this year's World Cup. Also citing that result four years ago, Schweinsteiger said the Argentines' body language and mentality in this Cup displays a disrespect to both referees and opponents, a claim to which Diego Maradona and his squad are not likely to take kindly (Tevez already has claimed round-of-16 opponent Mexico played better football than Germany). The aftermath of Schweinsteiger's comments could make this match all the more interesting.
Germany 3, Argentina 2. The popular pick is Argentina, with its three-pronged attack containing Tevez, Higuain and Messi. Yet the Germans, when they play well, look as though they can outplay any team in the tournament. In a high-energy, likely somewhat frantic affair, Ozil will provide the difference and squeak out a win for Germany.
Rachel Ullrich is an editor for ESPN.com.