HOUSTON -

Houston Dynamo's David Horst offers up a preview and prediction of Sunday's US vs. Portugal World Cup game.

PREVIEW

At the start of the World Cup no one would have guessed that the US would hold their fate in their own hands, but after a dramatic win against Ghana, the US has put itself in prime position to advance out of Group G. With a win over Portugal, the US would guarantee itself a spot in the round of 16, eliminate the Portuguese from the tournament, and avoid a must-win 3rd game against Germany. The theme of this World Cup has been that anything can happen, so can the US seize this chance and move to the top of the Group of Death?

KEYS TO THE GAME

Injuries: Is it the weather? Is it the ever increasing length of domestic seasons? No one will ever know for sure why there has been a rash of injuries at this World Cup, but both Portugal and the US have been bitten by the injury bug. In the opening game, the US lost Jozy Altidore to a hamstring strain that will sideline him for the rest of the competition. Without Altidore in the lineup, Aron Johannsson or Chris Wondolowski will have to step up and fill the gaping hole left by Altidore. On the flip side, Portugal has lost not only one of its starting defenders, Fábio Coentrão, but they have also lost their starting forward Hugo Almeida for the rest of the tournament. The biggest question mark going into the game, though, is the health of the world's best footballer, Cristiano Ronaldo. No one knows for sure just how healthy Ronaldo is, but lucky for Portugal, he's still pretty good at 75 percent.

Confidence: The US and Portugal could not have had more contrasting results after their opening games.   Right now the US is oozing confidence after a great performance against Ghana, while Portugal is reeling and trying to figure out what went wrong after their 4-0 defeat versus Germany. Confidence has nothing to do with talent or ability, but it's one of those intangibles that can either destroy a team or propel a team to new heights. Will the US team continue to believe in themselves, or will they let their guard down after such an emotional win?

PLAYERS TO WATCH

Cristiano Ronaldo: Arguably the best player in the world and one of the best to ever play the game. If he plays, what kind of effect will the injury have on him mentally and physically? In the opening game, he didn't seem like himself and disappeared for long stretches of time. If Portugal expects to win they need him to step up and be the same unstoppable force that he is for Real Madrid.

Tim Howard: When you're playing against the best offensive player in the world, you will need your goalie to come up big. Luckily for the US, they have Howard in goal. If Ronaldo is healthy and plays the way that we have become accustomed to then it's safe to assume that Howard will have a busy day. Howard has proven himself time and time again on the biggest stages that he is more than able to command the penalty area for the US.

Clint Dempsey: Thanks to a broken nose suffered against Ghana, Dempsey will now have a mask to go along with his super hero status. With Jozy Altidore going down hurt, and Landon Donovan being left at home, Dempsey now shoulders most of the playmaking and scoring duties. No matter what formation the US ends up playing, look for him to pop up all over the field and cause all kinds of problems for Portugal's make shift back line.

PREDICTION

Portugal is a wounded animal right now. They're coming off of one of their most embarrassing World Cup defeats, their defensive leader Pepe is suspended, and injuries have really taken a toll on their starting lineup. A wounded animal is still very dangerous, so it will be a hard fought, back and forth match, but look for a US team that is brimming with confidence to win this game 2-1.

Be sure to check out World Cup coverage on HoustonDynamo.com.