In Brazil, after wowing in the group stage, Messi seemed at times to be missing zip and incisiveness in later games. But the indications from Luis Enrique's debut league game as coach seem to be that the former Barcelona player, known for his firm hand and forthright manner, has rekindled Messi's fire.
Over the past two seasons, Messi slowly settled into a rut of waiting for the ball to come to him at the point of attack. The same was also true in some of Argentina's games in Brazil. This despite the fact that Guardiola once said the key to winning with Messi was making sure that he runs as much as possible.
Messi also has to watch his back. In signing Luis Suarez and Neymar over the last two years, Barcelona has attacking players who could challenge Messi's leading role if he becomes complacent.
With neither Neymar (injury) or Suarez (banned for biting an opponent at the World Cup) available on Sunday, Messi took full advantage to remind everyone that he is still the team's star.
Messi also must compete against himself. After recording unprecedented tallies of 73 goals for Barcelona in 2011-12 and 60 more in 2012-13, it felt -- ridiculously -- like a let-down when Messi "only" found the net 41 times last season.
Messi's double on Sunday left him on the cusp of another scoring record. At 27, he is only six goals from equaling Athletic Bilbao's Telmo Zarra as the Spanish league's all-time leading scorer with 251.
Still, it will be over the course of the entire season that Messi will again be judged. He can either further cement his place as one of football's all-time greats or risk talk of decline.
