Critics to closely study Maradona's decisions and tactics

Argentina's Lionel Messi heads into the World Cup as the player everyone wants to see but it will be the strengths and weaknesses of coach Diego Maradona that will determine how far the South Americans progress.

Argentina are clear favourites to top Group B ahead of Nigeria, Greece and South Korea but the critics will be looking closely during their opening games to see if Maradona, an inexperienced coach, has finally got the balance right.

He was often at the centre of controversy in the World Cup as a player - his 'Hand of God' goal in the 1986 finals, which Argentina went on to win, and expulsion at the 1994 tournament due to a failed doping test ensured he hogged the headlines.

But this time it his decision making that is under scrutiny and he certainly has not played safe -leaving out experienced Inter Milan pair Javier Zanetti and Esteban Cambiasso.

There have been signs, though, that Maradona's team have put their shaky qualification form behind them and the abundance of talent in the squad, particularly the outstanding Messi, puts them among the genuine contenders for the title.

Nigeria are their opponent's in the opening game of the group and the African side, who failed to qualify four years ago, are skippered by the experienced Nwankwo Kanu and have seasoned Swede Lars Lagerback in charge.

The Nigeria squad is packed with players performing weekly in the top European leagues which has given them the confidence to believe they can mount a strong challenge.

Greece showed when they won Euro 2004 that despite lacking big-name players, their German coach Otto Rehhagel can get the best out of a hard-working unit and they did well to fight past Ukraine in the World Cup qualification playoff.

It will be interesting to see, after the poor defence of their European title two years ago, whether the 71-year-old Rehhagel, at his first World Cup, can recapture the remarkable fighting spirit and tactical discipline of six years ago.

South Korea, semi-finalists when co-hosting the finals with Japan eight years ago, were less impressive in 2006 but they bring a team with plenty of European league experience such as captain Park Ji-Sung of Manchester United.

After being coached by Dutchmen Guus Hiddink and Dick Advocaat at the past two World Cups, they now have Korean Huh Jung-Moo in charge and he is expected to bring a more conservative approach.

Huh will come up against Maradona for the first time since they met on the field in the 1986 finals, when the Korean's tough man-marking led the Argentine to recently talk of his opponents playing "taekwondo not football".

Argentina can expect plenty of football from the Koreans this time.