Even if a club is ready to pay and barca allow him to leave, Messi will not leave barca ever. At the age of 13, Messi moved to barcelona having a serious problem in his growth hormones and he needed treatment. Barcelna were the only club in the world that offered to pay for the growth hormone treatment he needed at that time. After that, his body growth was normal, and he started his journey into the most complete soccer player ever. For that my friend Messi considers barca his first and not second home and will not leave in any way even if he receives 1 billion € salary.