Quite simply, Lionel Messi is the best player on the planet today. He looks so composed, so relaxed with the ball at his feet. He's just 22 years old (he'll turn 23 during the World Cup), yet plays like a veteran. He may not score the most goals during the next month because Argentina has so much attacking power, but you will tell your grandkids about him years down the road. If you have to choose one game and one player to watch, choose Lionel Messi.
Franck Ribery, France
Group A is one of the toughest to predict in the World Cup draw. You've got Uruguay, a team that played very well in CONMEBOL qualifying and boasts a star in Diego Forlan; Mexico, a team that traditionally is strong in group play; South Africa, the host nation, which has historically been as good as a straight ticket into the knockout round (though it may not be this year); and France, perhaps the biggest mystery of all. A team loaded with individual talent, Les Bleus would not have even made the World Cup finals if not for a hand ball by Thierry Henry that went uncalled in the playoff against Ireland. And you've got Franck Ribery. Without question one of the most talented players in the world, Ribery has been embroiled in a prostitution scandal that, for a while, left his World Cup status in doubt. It will be Ribery's responsibility to elevate his game, and to carry a squad that should advance. But this France team is just such a mystery. Worth watching.
Philipp Lahm, Germany
As he regularly shows at Bayern Munich, Philipp Lahm is one of the best right backs in the sport. But this will be a new test for him. When Michael Ballack went down with an ankle injury, Lahm was thrust into the role of captain for Germany. While that may not be as big a deal for some teams, Germany is a young team that needs leadership. Lahm's ability to provide that will determine how far Germany goes -- and, indeed, if they can get out of a very tough group with Australia, Ghana and Serbia.
Landon Donovan, USA
Remember: this isn't a list of the 10 best players, it's a list of 10 players you want to keep an eye on. For the U.S. to advance, Landon Donovan has to play extremely well. In his loan stint at Premiership side Everton this year, Donovan proved that he is a legitimate world-class player. But he was still a role player in England. For the U.S. to be successful (aka, advance to the second round), Donovan needs to dominate the midfield. He needs to control play, distribute, and at times he'll need to finish. The U.S. will only go as far as Landon Donovan takes them.
The easy choice for Brazil's 'player to watch' is Kaka. He's the most-hyped, and plays a central role on the pitch. But if you're watching a Brazil game on TV, keep your eye on the right back. Maicon is the most dynamic defender in the world, with an unparalleled ability to go forward and join the attack. He plays stellar marking defense, as well. It's easy to watch the strikers. It will be rewarding to watch Maicon.
Arjen Robben, Netherlands
The Dutch have the talent to win the World Cup. Their roster is stacked. But this isn't the first time that's been the case for Holland. The key to their success will be Arjen Robben. The winger is electric with the ball, and a danger to score every time he touches it. His ability to cut in from the flank and get off his rocket left-foot shot is a sight to behold. Unfortunately, he picked up an injury in Holland's 6-1 win over Hungary on June 5. He thinks he will be fine for the World Cup, and the Dutch are deep enough to survive group play without him. But they'll need him healthy if they have title aspirations.
Wayne Rooney, England
The Manchester United star had a superlative season for his club team, and led England in scoring during World Cup qualifying. He doesn't need to score to have a huge impact on the game, but he needs to have a huge impact on the game for England to make a deep run. He distributes the ball very well for a scoring striker, and can link up play as well as anyone. As goes Rooney, so goes England.
It's very difficult to decide who to watch on Spain. There are so many dynamic players, and the flowing style of football they play can leave you mesmerized (rather than focused). But if you are able to pick your jaw up off the floor, the man you need to track is Xavi. He's creative, but won't get fancy just for the sake of it. He's too smart for that. He controls the pace of the game, distributes with aplomb, and can put the ball in the back of the net when they need him.
Didier Drogba, Ivory Coast
Simply put, he is the best player in Africa. And you won't have trouble finding the Chelsea star on the pitch. He's big, strong, fast, and always a focal point when the Ivory Coast is in the attacking zone. He takes the free kicks, he has a rocket shot, and he's deceptively quick with the ball at his feet. The question now is ... will he be on the pitch when his team begins play on June 15? He broke a bone in his arm during a warmup match on June 4, and is now a serious doubt for his team.
Cristiano Ronaldo, Portugal
The 2008 FIFA World Player of the Year, Ronaldo combines everything that makes the sport fun to watch: speed, ball skills and a killer shot. He frustrates opponents, he's been known to dive, but he is simply electric. Portugal doesn't have a great squad top to bottom this year, but Ronaldo can produce goals out of nowhere, doing most of the work himself. When he's darting around in the offensive zone, he can almost single-handedly carry his team. There are not many players in the world about whom you can say that.