#3 Frank Rijkaard
Lionel Messi is now the best footballer in the world but he owes so much to Frank Rijkaard who oversaw his development during the early years of his career. Rijkaard was appointed Barcelona manager for the 2003-2004 season.
During this time, Messi was making waves at the team's youth level.
Rijkaard helped Messi to progress to the first team and ensured that his talents continued progressing. He introduced the genius into the team where he had the privilege to train with the best players of that time, including Ronaldinho, Samuel Eto'o, and Ludovic Guily.
He was finally handed his debut on November 16, 2003, in a match against Porto.
The manager ensured that he monitored the Argentine's development during his time at the club. They won many trophies together including the Champions League in 2006. He finally left the club in 2008, at a time when Messi was already a global star and made the Ballon d'Or nomination that year.