#2 Luis Enrique
He was appointed the manager of FC Barcelona on May 19, 2014, and worked with the club until June 30, 2017, when his contract expired. At the club, he had the privilege to train the greatest player in the club's career, Lionel Messi. Although their start was a bit controversial, they later had a perfect relationship.
During their time at the club, Enrique improved Messi's game by introducing some form of counter-attacking system with Neymar and Luis Suarez joining Messi to form a formidable attack. Their time of working together was marked with lots of success, winning 9 trophies collectively and Messi winning the 2015 Ballon d'Or along with other individual awards.
Enrique later left Messi and co. after seeing out his contract in the last summer but his time at the club was a joy to watch.