David getting the better of Goliath is always news, more so when it happens on the big stage and there is no bigger stage than the World Cup. Shock results have been part of World Cup folklore through the years.

How can one forget the USA stunning England in 1950, North Korea shocking Italy 1-0 in 1966, Algeria upsetting Germany in 1982, Cameroon beating Argentina in 1990 or Senegal defeating France in 2002? Saudi Arabia's defeat of Argentina on Tuesday is an unexpected result of the same magnitude.

For starters Argentina has a FIFA ranking of three to Saudi Arabia's 51. In head-to-head contests Argentina were ahead 2-0 with two draws. According to the bookies Lionel Messi's team were the second favourites to win the trophy after Brazil.

Most significantly Argentina were on a 36-match unbeaten streak one game away from equaling Italy's 37-match run in international football. Indeed the reigning Copa America champions hadn't lost a match in three years.

At half time things seemed to be moving according to expectations. Argentina led 1-0 thanks to Messi's tenth minute penalty but it could well have been 4-0 had the players not fallen repeatedly into the offside trap leading to three disallowed goals.

However things changed dramatically in the second half and two goals in five minutes saw Saudi Arabia ultimately pull the rug from under Argentina's feet. And a team that has suffered 5-0 and 8-0 defeats in the World Cup over the years roared back to complete an astonishing 2-1 victory that will rank as one of the greatest shocks in the 92-year-old history of the competition.

The bolt from the blue was not just a defeat for Argentina but was especially devastating for Messi for whom winning the World Cup is now an obsession. The one jewel missing from his crown the 35-year-old superstar was hoping to give off his best in what could well be his last chance to hang a World Cup medal round his neck.

After being rudely jolted from his happy dream Messi in his fifth World Cup admitted that it was "a hard blow for everyone, we didn't expect to start like this". It was also something hard to take for Lionel Scaloni, the Argentine manager.

He even tried a triple substitution late in the game in a last minute bid to salvage the situation but nothing worked leaving him to face the reality of a grim situation. ``We don't have any other choice but to get up and continue, we have to win the two remaining games. The World Cup doesn't give you time to be wrong''

All of course is not lost as yet for the men in blue and white. There are still two group games against Mexico and Poland and there is a lot of encouragement that they can take from history. They can look back at their own campaign in 1990 when as defending champions they went down most unexpectedly to Cameroon in their opening fixture and yet made it all the way to the final before losing to Germany.

More recently in 2010 Spain went one better. They had entered the competition, the first to be played on the African continent as the reigning European champions and as such were one of the favourites. However in their first match they suffered a shock 0-1 defeat against Switzerland.

The defeat put Spain on the brink of elimination but in their next two group matches they defeated Honduras and Chile to qualify for the round of 16. Here they defeated Cristiano Ronaldo's Portugal 1-0 and in the quarterfinal they prevailed over Paraguay also 1-0.

Spain then notched up victories by similar margins in the semifinal against Germany and in the final against the Netherlands to become the first nation to win the World Cup after losing their opening match. So it is not Mission Impossible for Argentina though with Mexico and Poland playing a goalless draw it will make matters that much more difficult.

For the moment though the spotlight is on Saudi Arabia who are enjoying their moment in the sun and their secure place in football history. Their French coach Herve Renard is clearly the man of the moment as one who inspired his team of lightweights to get the better of one of the game's heavyweights.

The 54-year-old Renard began to make his name as a coach in 2012 when he led Zambia to the African Nations Cup title for the first time during his second spell in charge of the team. He then moved on to manage Ivory Coast and led them to the African crown in 2015 with a dramatic shootout win over Ghana before taking Morocco to the World Cup for the first time in 20 years.

Renard is not only astute in matters of strategy and tactics but is also acknowledged to be a powerful motivator. It was the second quality more than the first that was more in focus on Tuesday.