Messi, who won the Ballon d'Or in 2010 and was the FIFA World Player of the Year for 2009 as well, is on a three-man shortlist for this year's award, which also includes Barca team-mate Xavi and Real Madrid striker Cristiano Ronaldo.
He enjoyed a stellar 2011, helping Barcelona to Champions League and Spanish La Liga glory, scoring 31 goals in La Liga alone. In the 2011-12 campaign he has already scored a further 17 league goals, an incredible statistic for a player who is not an out-and-out striker, and Pique believes the 24-year-old is without equal on the planet.
He told La Vanguardia newspaper: "(Messi) is leading the team to be one of the best ever - it is thanks to him that we have won so many titles.
"It is a pleasure to have him play for us, and he plays the same way as he did when he was 13, only now he does it more professionally and against the very best.
"We can only hope he keeps his level up for the maximum time - if he can improve that would be great. But we should not ask for anything more, and if he continues his love for the game it will keep him at the top for many years.
"It takes many years to get to the top level, and Leo is the best in the world."
Barca playmaker Xavi has been recognised for his key role in dictating the team's rhythm, while Portuguese forward Ronaldo's goalscoring form was awesome for Real in 2011, scoring 40 league goals last season and having already added 21 in the current campaign.