Doha (AFP) - Robert Lewandowski scored the first World Cup goal of his career as Poland brought giant-killing Saudi Arabia back down to earth on Saturday while Argentina and Lionel Messi prepared for a fight for survival against Mexico.
Barcelona striker Lewandowski, who had failed to score in four previous World Cup games, netted the second in a 2-0 win in the Group C clash at the Education City Stadium.
It was a World Cup reality check for the Saudis, who had stunned Argentina 2-1 in their opening game.
"The importance of the goal and how I scored it made all my dreams from childhood come true," said Lewandowski, who missed a penalty in Poland's opening 0-0 draw with Mexico on Tuesday.
The 34-year-old was overcome with emotion having capitalised on a blunder by midfielder Abdulelah Al-Malki.
"I think the older I get the more emotional I get," Lewandowski said."I'm aware it might be my last World Cup and I wanted to be able to say that I've played and scored at World Cups.
"The result is most important, but getting both is great."
Goalkeeper Wojciech Szczesny was the hero for Poland, however, producing a stunning double save in the first half.
He first denied Salem Al-Dawsari from the penalty spot, then made a stunning stop to keep out the rebound.
In other early games on Saturday, Australia defeated Tunisia 1-0, recovering from a chastening opening defeat against defending champions France to keep their hopes alive.
Striker Mitch Duke scored the only goal of a tight game with a clever header in the first half and Australia desperately held on to silence Tunisia's vociferous fans.
The Socceroos sit second in Group D with three points from two games, with a game to come against Denmark.
"As a striker you need to have that confidence and believe that you can score in every match," said Japan-based centre-forward Duke, 31.
France eye last 16
France can become the first side into the last 16 with victory over the Danes later Saturday.
Veteran forward Olivier Giroud needs just one more goal to become France's all-time top goalscorer.
Saturday's final match sees Argentina attempt to resurrect their World Cup hopes in a crucial clash with Mexico.
The two-time world champions, who arrived in Qatar on a 36-match unbeaten run, are in a precarious position after their stunning opening loss to Saudi Arabia.
The Argentines said they would draw on memories of superstar Diego Maradona, their 1986 World Cup-winning captain who died two years ago this week, to inspire them against the Mexicans.
"We keep him in mind.He was a very important person in world football, and not just for us Argentines," said Inter Milan forward Lautaro Martinez.
Argentina are not the only footballing giant fighting for survival at the World Cup, with Germany facing a must-win battle against Spain on Sunday in Group E.
Germany, beaten 2-1 by Japan in a remarkable opening upset, would be eliminated if they lose to the 2010 champions and Japan avoid defeat to Costa Rica.
Germany coach Hansi Flick described the game as his team's "first final of this World Cup."
"I am convinced of our ideas," Flick said."We will approach the game with courage and belief in our quality."
Spanish counterpart Luis Enrique said his team were looking forward to the "beautiful challenge" of facing the wounded Germans.
"I have a lot of respect for their players, they are world-class and their history is there to see," Enrique said.
"But we have the conviction that we have to beat Germany."
