The people of Argentina have been rapidly revising that opinion since this World Cup kicked off with Messi scoring sublime goals for fun, which he continued to do yesterday.
His brace, which included a sumptuous free-kick, inspired Argentina to beat Nigeria 3-2 and ensure qualification to the knockout stages as winners of Group F.
Messi's two goals were twice cancelled out by Nigeria's Ahmed Musa but Marcos Rojo's second-half finish made sure Argentina took all three points. Despite their defeat, Nigeria also progressed to the last 16 due to Iran's 3-1 loss at the hands of Bosnia & Herzegovina.
Messi's double means he is now joint top-scorer with Neymar on four and while the No.10 was substituted and spared the final half-hour of the game, his form carries Argentina into the last 16 in high spirits.
It took less than three minutes for the South Americans to break the deadlock. Javier Mascherano fired an incisive pass to Angel Di Maria and while the winger's shot was saved by Vincent Enyeama, the ball cannoned back off the near post and into the path of Messi - who shot high into the net.
One minute and 20 seconds later, however, Nigeria were level. Michel Babatunde broke from midfield and played the ball left to Musa, who skipped inside Pablo Zabaleta before curling the ball brilliantly past Romero and into the far corner.
Sergio Aguero's injury-plagued season continued as the Manchester City forward hobbled off in the 37th minute and was replaced by Ezequiel Lavezzi. On the stroke of half-time Messi chipped a free kick over the Nigerian wall to make it 2-1.
Nigeria drew level soon after the break as Musa ghosted through the Argentina defence before slotting past Sergio Romero. Rojo diverted a corner home with his knee to secure Argentina's third straight success.