WHAT'S ON THE LINE
It's only the first game of the group for both, but Argentina expects nothing less than a win. Even that might not be enough: A loss would be calamitous, a draw not much better, and a narrow victory only marginally satisfying. Yes, the pressure is on Diego Maradona and his bunch.
Lionel Messi added to the expectations when he recently said that, man for man, there's no better side in the tournament. While getting Argentina out of the way first is good, if Nigeria loses, as expected, and the other Group B opener, South Korea and Greece, produces a winner, the Super Eagles will be in a hole. The Nigerian president probably wants a victory -- he expects the team to win the whole thing.
STYLE AND TACTICS
Nigeria, under veteran Swedish coach Lars Lagerback, will probably bypass a 4-3-3 formation for a more defensive 4-4-2. Don't be surprised if he goes for a 4-5-1. Nigeria, more cautious than in years past, will look to clog the midfield and hit Argentina on the counter.
For all its talent going forward, don't forget that Argentina under Maradona places a premium on defense. The manager took ample joy in beating Germany in a friendly earlier this year -- in Germany -- 1-0. Look for a 4-4-2 or 4-3-3. Messi can't be shackled, so perhaps he'll play behind a front two of Diego Milito and Carlos Tevez.
PLAYERS TO WATCH
Lionel Messi, Argentina. Messi, on course to repeat as world player of the year following another great season at Barcelona, continues to be the brightest star on the jam-packed Argentinean team. One on one, he's the worst opponent for defenders. Is this Messi's breakout at international level?
Obafemi Martins, Nigeria. He's playing in his first World Cup but the speedy striker has a wealth of experience, plying his trade in Serie A, the Premier League and Bundesliga. Martins figures to be the main outlet on the counter. His long-range shooting ability makes him a threat inside and outside the box.
WHAT WE CAN EXPECT
The opening 30 minutes is vital. If Argentina nets an early goal, the Nigerians will be forced to play more open, allowing Messi and pals to roam free in space and score more. It could get ugly. However, if the game is scoreless at halftime and early in the second, dare we say a little panic might set in for the favorites? In that case, too much pressing will lead to great opportunities on the counter.
Also of note: John Obi Mikel's absence is a huge blow to Nigeria, lessening the midfield cover.
The book is still out on Diego the manager. Here's a guy who's called up more than 100 players in his brief time in charge. Can he get the substitutions right if the game is tight? Lagerback is a cooler head, and he's coached at the World Cup before, in 2002 and 2006 with Sweden.
Argentina will wear down Nigerian resistance and claim three points with a 3-0 win.
London-based Ravi Ubha covers soccer and tennis for ESPN.com.