4 Questions for the 2014 World Cup Semifinalists

The semifinalists' toughest challenges could come from within.

— -- After very nearly seeing his country's World Cup "mission" cut infamously short by Chile in the round of 16, Brazil coach Luiz Felipe Scolari told reporters at a post-match news conference that the hosts needed to bear down and roll up the welcome mat.

"We are being very cordial, very nice and polite to the foreign teams," he said, "but perhaps it's time for us to change."

The Brazilians answered Scolari's call in the next match, its July 4 quarterfinal clash against Colombia. The Seleção came out kicking, targeting the ball only occasionally. More often they seemed to take aim at young star James Rodriguez and his nifty Colombian teammates.

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Spanish referee Carlos Velasco Carballo, apparently overwhelmed by the big game, lost his grip on the proceedings and hundreds of millions of viewers saw the tournament's most heavily anticipated match descend into what German manager Joachim Low described on Monday as a string of "really brutal and crude fouls."

A little more than three days later, as Brazil contends with the loss of their beloved Neymar to injury, this semifinal round emerges in a fog of doubt.

These are the four biggest questions facing the four remaining teams in the World Cup semifinals:

With Neymar Injured, Does Brazil Have a Plan B?

As we learned in the quarterfinal, Brazil aspires to one thing: win the World Cup at the Maracanã this Sunday. The most "beautiful game" -- even for this many-splendored footballing nation -- is the kind that ends with the home team having scored more goals. Now, just two victories from "heaven," the plan, to the extent one exists, is to ride a second wave of patriotic emotion -- the first one, perhaps too strong, is now being managed by a professional -- and use Neymar's absence as a unifying force.

Here, again, is Brazilian coach "Felipão" on how his team views the challenge ahead: "Neymar has left us and has left a lot of himself with us, and he’s taken a lot of us with him. We’ve left behind that phase of being sad. We’ve accepted he won’t be with us anymore. After we accepted that, the way he spoke to the players made the squad understand that he had done his share. Now it’s up to us to do our share: myself, the other players and all the Brazilian people. We’ll be playing this match not just for ourselves but for our country, for everything we’ve ever dreamed of but also for Neymar and everything he’s done for us."

So, ready to throw on a yellow shirt and kick something? Brazil will have 11 men bursting at that opportunity this afternoon versus Germany. Whether they can keep their discipline -- a stacked midfield will be asked to methodically disrupt German possession -- and nerve against one of the world's most tactically diverse teams remains to be seen.

Which German Team Shows Up in Belo Horizonte?

"Football is a simple game," England's star striker turned broadcaster Gary Lineker famously explained. "Twenty-two men chase a ball for 90 minutes and at the end, the Germans win."

Manager Joachim Low's side has put the old truism to the test the past few weeks, but the results have come as advertised: Low plays captain Philipp Lahm in midfield, the Germans win. Low plays Lahm at right back, the Germans win, but more convincingly. Low inserts Sami Khedira alongside Bastian Schweinsteiger in the midfield, with Lahm again at right back, and the Germans shutdown and knock out a France team that had scored 10 goals in its first four matches.

Despite the unerring results, this Germany team remains a bit of a mystery. It has been 24 years since die Mannschaft lifted the World Cup and the pressure back home to end the unusual streak is building. The quarterfinal defeat of France was impressive, but hardly inspiring. Still, whatever team shows up in Belo Horizonte today, it's hard to imagine them leaving without a win.

How Much Will Leo Messi Miss the Injured Angel di María?

You'll have to ask Gonzalo Higuain and Sergio Agüero, and their manager, Alejandro Sabella. The latter will decide which, if not both, of the two will be deployed alongside the little maestro in Wednesday's semifinal against the Netherlands.

The uneven Argentine attack finally seemed to have found its rhythm when di María was forced to exit their quarterfinal defeat of Belgium with a thigh injury. As we saw in the European Champions League final, di María might not be a star in his own right, but he knows how to keep himself in their orbit, a talent that helped Real Madrid and now La Albiceleste achieve a celestial flow.

In his absence, Argentina will hope Messi can, once again, make sense of his chaotic chorus of teammates. Bet on Higuaín to start. He scored early against Belgium and his near-miss later in the match caused this awesome thing to happen.

What Else Does Dutch Manager Louis van Gaal Have Up His Sleeve?

Not too shy to show a team what he's got down his pants, van Gaal has been this World Cup's most impressive tactician. He used a water break during his team's Round of 16 match with Mexico to flip the script and mastermind a now famous come-from-behind victory. And his wager that backup goalkeeper Tim Krul's 6-5 frame and aggressive facial expressions would psych out the Costa Ricans during their penalty shootout in the quarterfinal was a big winner.

Next up, though, is Messi. Since there is no known way to stop Messi when he's on the ball, van Gaal has likely spent the past few days trying to devise an elaborate game of keep-away. He has one more day to perfect the plan.

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