The 2018 FIFA World Cup has got off to a stunning start.
The first round of the group stage has thrown up huge surprises.
Defending champion Germany suffered a shocking defeat -- its first in a World Cup game since the semi-final loss to Spain in 2010 -- while Brazil, Spain and Argentina -- the other pre-tournament favourites -- also failed to win their opening round matches.
A look at how the big teams performed in their opening games:
Germany shocked by Mexico
Germany -- the defending champions -- crashed to defeat in their first game at the World Cup on Sunday, June 17, as an enterprising Mexico clinched a 1-0 victory in a thrilling Group F opener.
A shaky warm-up campaign had called into question the dominant form the Germans showed in qualifying, but experience and records were on their side, having won every opening game at major tournaments since Joachim Loew took over as coach in 2006.
Juan Carlos Osorio's side had other ideas, however, holding their own against the favourites' fearsome but slowing midfield and finding space at the back and seeking to end 33 years without a win against Germany.
After wasting a handful of first-half chances while living dangerously in their own half, Hirving Lozano's 35th-minute strike on the break proved just reward.
The Germans, branded an 'embarrassment' in their home press, should still qualify, with their next two matches agaisnt Sweden and South Korea.
And there is plenty of historical precedent for teams going on to do well after losing an opening game.
But their reputation is not what it was. And coming second could well see the four-times champions face five-times World Cup winners Brazil if the latter win Group E.
Spain held by Portugal
Portugal Captain Cristiano Ronaldo scored a remarkable hat-trick to earn his team a 3-3 draw in an enthralling clash with neighbours Spain.
In an entertaining game, Ronaldo twice put Portugal in front, Diego Costa replied each time, Nacho gave Spain the lead with a stunning volley and Ronaldo then had the last word with a superb free kick he won himself.
Ronaldo has a relatively poor free-kick record for Portugal and when he and Raphael Guerreiro both stepped up in the 88th minute, many of their fans might have hoped the left back would have been allowed to have a go instead of his skipper.
Instead, Ronaldo stood with his legs apart in familiar pose, rolled up his shorts and curled an exquisite effort around the Spain wall and into the net past the helpless David de Gea.
The 33 year old, who took his tally to 84 goals in 151 games for the European champions, became the fourth player to score in four World Cups after Pele and Germans Uwe Seeler and Miroslav Klose.
He also became the first player to score in eight major tournaments in succession after hitting the target in the last four European Championship tournaments.
The goal denied Spain what would have been a morale-boosting win after a traumatic and extraordinary week which saw coach Julen Lopetegui sacked barely 48 hours before kick off in the Group B game.
The Spanish federation said Lopetegui had negotiated a contract to take over as Real Madrid coach without its knowledge, and replaced him with Fernando Hierro who took charge on Friday.
Argentina struggle against Iceland
Tiny Iceland made a stunning impact in their first-ever World Cup on Saturday when they held 2014 runners-up Argentina to a pulsating 1-1 draw.
Lionel Messi's tournament began wretchedly as he saw his penalty saved by Hannes Halldorsson.
Sergio Aguero gave the two-time world champions the lead after 19 minutes before Iceland, showing the same commitment and self-belief that saw them stun the soccer world with their run to the Euro 2016 quarter-finals, hit back four minutes later through Alfred Finnbogason.
Argentina, playing in all-black and roared on by the vast majority of the crowd in a rocking Spartak Stadium, eventually took command, delivering wave after wave of attacks in the second half.
Yet the Argentines actually created few clear chances either side of the poorly-struck 64th-minute penalty by Messi, who drew a blank despite a remarkable 11 shots during the match.
Man of the Match Halldorsson said he had done his homework on Messi, who has now missed four of his last seven penalties for club and country.
"I looked at a lot of penalties by Messi and I also looked at how I had been behaving in previous penalties, so I tried to get into their mindset, how they would be thinking about me," he said.
Brazil manage draw against Switzerland
Brazil joined other big guns who failed to fire in their opening World Cup game as lax defending from a corner allowed Switzerland to cancel out Philippe Coutinho's spectacular curling strike and grab a 1-1 draw on Sunday.
The five-times world champions took a deserved lead midway through the first half in the Group E game when Coutinho's irresistible long-distance shot cannoned in off the far post, but Tite's side, who had looked so impressive in the tournament build-up, did not build on their advantage.
The highly organised Swiss hit back early in the second period from one of their few chances as Brazil's Casemiro and Miranda switched off and the unmarked Steven Zuber barely had to leave his feet to nod in Xherdan Shaqiri's whipped corner.
Brazil went all out in pursuit of a winner and came agonisingly close to finding it as Coutinho and Miranda lashed wide from inside the area while Neymar and substitute Roberto Firmino were denied by Swiss goalkeeper Yann Sommer.
It was the first time Brazil had not won a World Cup opener since drawing 1-1 with Sweden in the 1978 tournament.
France were the only one among the fancied teams who got off to a winning start, despite an under-par display against Australia.