"I know that the moment I feel that I am no longer ready to perform, that I no longer enjoy myself or help my teammates, I will quit," Messi told the Big Time podcast.
"I am very self-critical with myself, I know when I am good, when I am bad, when I play well and when I play badly. When I feel it's time to take that step, I will take it without thinking about age. If I feel good I will always try to continue competing because that's what I like and what I know how to do".
Despite the talk of retirement, the eight-time Ballon d'Or winner has yet to consider what he will do when he does hang his boots up. "I have not yet thought about what I will do when I retire, today I try to enjoy the day to day, the moments, without thinking about the future. I don't have anything clear yet, I hope to continue playing for a while longer, which is what I like.
"When the time comes, I will surely find the way to do what fulfils me and what I like and a new role. On a sporting level I was lucky to be able to achieve all my dreams and the truth is that I can't ask for more."