Guardiola lauded the contribution of Messi to the success of his side over the past four seasons.
"He is more competitive than when he arrived and I have learned from him," said Guardiola.
"Without him we would have won titles, but it would have been almost impossible to win 14 out of 19.
"I hope that I have helped in some way if that was possible. It has been a privilege to train the best player I have seen and will ever see."