Fourteen of the South Korea squad are 25 or younger.
They have won just one of their last six games and conceded 12 goals in the process.
Manager Hong Myung-bo, captain and key defender of South Korea's 2002 semi-final team, has been working hard to try and shore up that issue.
Goal! (28 mins)
Korea 0-1 Algeria
What have you done keeper?! Gifted a two-goal lead to Algeria, that's what. From the corner central defender Rafik Halliche rises leaps like a salmon and nods the ball powerfully into an empty net, as keeper Jung is stranded in no man's land.
Got to be more derisive in the box from Jung there but a great finish none-the-less.
That's got Korea going - both the football team, their fans and the country. This is how to support your team from the other side of the world at 5am.
Here comes the Twittersphere. I was going to do my own joke but this is much better. Well done Jack.
Portugal V USA - huge match
USA: Howard, Johnson, Cameron, Besler, Beasley, Beckerm, Jones, Bedoya, Bradley, Zusi, Dempsey
Portugal: Beto, Pereira, Alves, Costa, Almeida, Moutinho, Veloso, Mierles, Nani, Postiga, Ronaldo
Jurgen Klinsmann has asked his USA team not to be intimidated by the Champions League players opposite them who are fighting to stay in the tournament .
Kick-off is go go go!
Whatever they say about the temperatures in the Manaus stadium at the heart of the rain forest, one thing not up for debate is its beauty. Stunning evening with a purple sky, undamaged by pollution.
If Portugal win, they are level on points with the USA - a result that Ghana would certainly enjoy. Group G has certainly been the most entertaining so far, following Germany's enthralling 2-2 draw with the Africans yesterday.
USA 0-1 Portugal
One error from the US separates the teams at the half-way mark.
Here are the stats:
USA 50% - 50% Portugal
USA 9 - 9 Portugal
USA 4 - 2 Portugal
Get the feeling that the game will be decided by which game makes the fewer mistakes. Pretty average so far but all to play for. Let's see if we can get another electric second-half, as per our expectations at this World Cup!
Behavior that we completely endorse at Al Jazeea English Sport....
However, we simply cannot condone such imagery as this Maggie. Either way, we know CR7 turns heads.
Close! (55 mins)
USA 0-1 Portugal
That was the chance! Fabian Johnson misses a perfect opportunity to score after a superb through run past the Portuguese defense. He is really looking to be a quality player.
The USA are really sensing blood now - it's going to be a cracker-jack finish. Fans going crazy in the Amazon. Win or lose, it will be a night to remember for this lot.
There was something Roberto Carlos-esque about that goal from Jones. I think the good people of Twitter enjoyed it.
Booking! (76 mins)
USA 1-1 Portugal
Booking for Jermaine Jones after a crunching tackle on Joao Moutinho. Have Portugal got nothing more to give? Certainly playing with a very lethargic manner at the end of this game.
Bit dramatic, but Dempsey is certainly playing like something out of a dream in this tournament.
GOAL! (90+5 mins)
USA 2-2 Portugal
Portugal's man has finally delivered in the World Cup. Not a goal but a pin-point cross from the touch line for Silvestre Varela to put away with a powerful header that Howard had no chance of saving.
USA fans and players are devastated, as you might understand, but can still hold onto the fact that they sit second in the group.
USA 2-2 Portugal
The USA have been involved in the most dramatic finishes in the World Cup so far but this time, it was their turn to be disappointed at the end.
Portugal are still alive, but only just.
Welcome back to the Brazil live blog.
It's going to be a busy one this evening with the two early games both kicking-off in 15 mintues and two more in four hours time.
We will have all the usual match action mixed in with some interesting statistics and great pictures from around Brazil.
Let's get to it!