The U.S. men's national team will face Lionel Messi and Argentina on Tuesday in a Copa America semifinal match in Houston.
Argentina is No. 1 in FIFA's world rankings and the U.S. has only prevailed twice in a head-to-head matchup — most recently in a 1999 friendly.
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Here are three keys to U.S. hopes of an upset Tuesday night:
1. How will the USMNT cope with all of its loses? The appeals to get Jermaine Jones and Bobby Wood back on the pitch never really had a chance. Jones was given a red card against Ecuador for putting his hand on the face of an opponent and was sent off for it. Wood earned his second yellow of the tournament moments later on a rash challenge. Neither will play in Tuesday's game. Starting Midfielder Alejandro Bedoya is also out with two yellow cards.
So who will replace them in Jurgen Klinsmann's tight-knit starting lineup?
Kyle Beckerman will likely step into Jones' place as the holding midfielder. He has made a couple of appearances late in games as a closer to hold off the opposition. He would be a like-for-like replacement to Jones. Graham Zusi seems like a logical replacement for Wood. Zusi, like Beckerman, has earned time in the Copa already and has even scored a goal. He is more of an attacking midfielder than an outright forward like Wood, but he would still be a positive addition to the lineup as an attack-minded player.
The final spot is tricky. Bedoya's role was as a wide-ranging midfielder who moved up in attack and also had a fair amount of defensive responsibilities. With DeAndre Yedlin back in the squad after serving his suspension and Matt Besler proving he can go toe-to-toe with this level of competition, it's possible Klinsmann could slide Fabian Johnson into the left midfield spot — a position he plays for his club team in Germany. That would allow Johnson, Besler and Yedlin all a chance to start.
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2. Can anyone stop Lionel Messi? The short answer is yes — Atletico Madrid proved that in the Champions League this year. But the real question is can anyone on the USMNT stop Messi? Arguably the world's top player, Messi has been in scintillating form at the Copa despite limited playing time.
With four goals already to his name, Messi will certainly be expected to add to that mark in just his second start. He is quick, great with the ball at his feet and always in the mood to make a challenging run and either score himself or pick out a perfectly weighted pass.
Luckily for the USMNT, center backs John Brooks and Geoff Cameron have been two of its best players in this tournament. They are both physically imposing players who could knock Messi off the ball and disrupt Argentina's pristine passing game.
3. Will Darlington Nagbe or Christian Pulisic make an impact? Fans of the USMNT have been drooling over the prospect of watching Pulisic — a 17-year-old star at Borussia Dortmund — weave his way through opposing defenses, or Nagbe control a midfield like he has shown he can in MLS.
But so far, neither has made much of an impact in this tournament, with both reduced to just a few minutes off the bench in the first game. Now, with three players suspended, Pulisic and Nagbe find themselves in a position to potentially start or be priority subs off the bench. In a game that's expected to be close despite the lopsided FIFA rankings, their impact could change the course of the game.