A World Cup that has defied all expectations reaches its climax on Sunday when Lionel Messi could join Diego Maradona in Argentine immortality by taking the south Americans to the title or France could become the first nation to retain it since 1962.

Both scenarios would be an appropriate final act to the first World Cup staged in an Arab country.

But whatever happens, a tournament ridiculed in the build-up and which began a little awkwardly delivered an exhilarating rollercoaster ride that even the cynics leapt on board.

Millions of words were written criticising the choice of Qatar as host to the world's second-largest sports event and the debate will continue long after the last ball is kicked.

But for a month the so-called beautiful game did, in the words of FIFA president Gianni Infantino, spread some joy.

The marquee names of Messi, Kylian Mbappe, Neymar and Cristiano Ronaldo delivered storylines. Saudi Arabia, Japan, South Korea and Tunisia delivered shocks. New heroes emerged.

Yet the abiding memory for many will be Morocco's shake-up of football's hierarchy.

Thousands of their fans painted the desert red and turned Doha's souq into a corner of Marrakesh as the Atlas Lions roared into the semi-finals.

Harnessing the energy of their followers, Walid Regragui's men scored victories over European aristocrats Belgium, Spain and Portugal on the way to becoming the first African and first Arab country to reach the last four.

France proved a match too far as they set up a showdown with Argentina in the spectacular Lusail Stadium where nearly four weeks earlier Argentina's 2-1 defeat by Saudi Arabia lit the blue touchpaper for an extraordinary tournament.

In five second-half minutes Saleh Al-Shehri and Salem Al-Dawsari wrote themselves into Saudi sporting folklore by scoring the goals to overturn a Messi penalty and seal the biggest statistical shock in World Cup history.

Infantino, who raised eyebrows on the eve of the tournament with a passionate monologue defending the Qatari organisers, described the group phase as the best ever. Few would disagree.

The 48 games produced 120 goals, only two red cards, and enough head-spinning moments to garnish three tournaments.

A day after Saudi Arabia's win, Japan came from a goal down to beat Germany -- a result the four-time champions never recovered from as they went home early.

Iran, against a backdrop of widespread anti-government protests at home, were smashed 6-2 by England, then beat Wales with goals in the eighth and 11th minutes of stoppage time.

Late goals and hasty re-writes for the world's written media were a recurring theme and the last three nights of group action were a white-knuckle ride on and off the pitch.

Japan stunned Spain in a stomach-churning finish to Group E which at one point looked to be sending Costa Rica and Japan into the last 16 at the expense of Spain and Germany.

South Korea conjured a stoppage-time goal to beat Portugal and make it out of Group H to the heartbreak of Uruguay while Mexico's manic attempt to score enough goals against the Saudis to pip Poland to second spot in Group C ended in failure.

Every continent was represented in the last 16 for the first time but after such a riotous group phase would it fall flat?

No chance.

Australia gave Argentina a mighty late scare, Mbappe dazzled for France against Poland and a free-scoring England ended the Senegalese party in the tent-like Al Bayt Stadium, one of seven new stadiums built for the tournament, including the 974 Stadium comprised of recycled shipping containers.

Brazil danced their way to a 4-1 thrashing of South Korea while Portugal did the unthinkable and left out Ronaldo only to find a new hero as Goncalo Ramos bagged a hat-trick in a 6-1 rout of Switzerland.

Morocco went toe-to-toe with Spain in an absorbing 0-0 draw, then knocked out the 2010 champions on penalties as Luis Enrique's side failed to net a single kick.

Unpredictable as the tournament was, the usual suspects assembled for the quarter-finals.

Some Neymar magic gave Brazil an extra-time lead against Croatia, only for Bruno Petkovic to level in the 117th minute with Croatia's first effort on target. Almost inevitably, Brazil slumped out on penalties.

Argentina squandered a 2-0 lead against a Netherlands side who dumped their usual scientific approach in favour of lumping high balls into the box to destructive effect.

Wout Weghorst's brace, the second in the 11th minute of stoppage time silenced the blue and white hordes, but Messi and Co edged a penalty shootout to decide a fractious contest.

Ronaldo became the first man to score in five World Cups but his last appearance, again as a substitute, ended in tears as Portugal went down 1-0 to a history-making Morocco.

England's penalty curse then returned as Harry Kane's botched effort condemned them to a 2-1 defeat by France.

Messi, channelling his inner-Maradona, inspired Argentina to beat Croatia and few would begrudge the diminutive number 10's record-breaking 26th World Cup appearance ending with him holding aloft the gleaming trophy.