Lionel Messi helped keep Argentina's World Cup bid alive with the first goal in a 2-0 victory over Mexico on Saturday.

Defeat to outsiders Saudi Arabia in their opening Group G match in Qatar had left Argentina on the brink, knowing another loss would spell the end of their tournament chances.

But the Albiceleste just edged a disjointed and tetchy affair against their fellow Latin Americans at the Lusail stadium in Doha.

And who else but the mercurial Messi should be the hero, firing home a low shot from 20 yards on 64 minutes, before Enzo Fernandez added a thunderbolt second goal for Argentina three minutes from time.

Messi's goal meant he tied fellow Argentine icon, the late Diego Maradona, on eight goals and 21 appearances at the World Cup for Argentina.

The goals were two rare moments of quality in a poor and tense encounter where the occasion seemed to get to everyone, except seven-time Ballon d'Or winner Messi.

But Argentina still need to win their final group match against Poland to guarantee a place in the knock-out stages.

Earlier, Robert Lewandowski scored the first World Cup goal of his prolific career when he netted in Poland's 2-0 win over Saudi Arabia, bursting their bubble following the team's giant-killing act against Argentina.

Barcelona forward Lewandowski was almost overcome with emotion after making sure Poland took a big step towards the last 16 in Qatar when he rolled home in the 82nd minute after being gifted the ball by Saudi midfielder Abdulelah Al-Malki.

The goal banished memories of his missed penalty during the Poles' opening stalemate with Mexico and ensured Poland moved top in Group C.

"I was not surprised (about Lewandowski's reaction) because I know how deeply he felt about the last match," said Poland coach Czeslaw Michniewicz.

"He didn't score in (the) first match but he could have had a hat-trick today. We're very happy with him, just as we were very sad with him after (the) missed penalty."

Poland are a point ahead of Saudi Arabia thanks also to Piotr Zielinski's roofed finish and an incredible double save from Wojciech Szczesny after Salem Al-Dawsari's penalty late in the first half. (AFP)