In danger of missing out on a World Cup finals for the first time since 1970, the return of Lionel Messi could not be more crucial for Argentina.

Two wins from their last seven Qualifiers has seen the two-time World Cup winners - ranked third in the world by FIFA and on their third coach of the qualification process - leave themselves with a worrying run-in to come.

Sitting fifth in the CONMEBOL standings with four games to go, Argentina would miss out on an automatic qualification spot as it stands, and instead face the winner of the Oceania qualification process (most likely New Zealand) in a play-off to ensure they can plan for a summer in Russia.

Even that eventuality isn't guaranteed, however. Ecuador are two points behind Argentina ahead of Thursday's round of fixtures, and Jorge Sampaoli's first World Cup Qualifier seems a daunting one, as Argentina travel to Montevideo to take on third-placed Uruguay.

But there is hope, in the shape of a returning hero. Messi's own World Cup qualification campaign looked to be over, as he was handed a four-match suspension for abusing an assistant referee in Argentina's 1-0 victory over Chile in March.

The hysteria completely overshadowed their next match high in the altitude of La Paz, as Bolivia swept aside their opponents with ease, ultimately bringing an end to Edgardo Bauza's disappointing reign. Argentina, without their talisman, were simply not the same force.

Now, with that ban overturned on appeal, optimism is high once more, and despite a multitude of talent available to Sampaoli, the significance of Messi's return has not been lost on the former Seville boss.

"I have had the good fortune to arrive with the national team at the time that Messi's ban was lifted," Sampaoli said last month. "We have the best player in the world [in Messi]. From him the team is born."

"To leave Messi alone at this moment is a mistake. We need to surround him with the best players possible," he said, while acknowledging that "there are no players who have more privilege than others" with the exception of Messi.