Andre Agassi would not have come back to tennis if it weren't for Novak Djokovic, a player he believes still has many other grand slam titles to win, the American said.
The 47-year-old agreed to coach Djokovic, who has been through a crisis of confidence since winning his 12th major title at the French Open last year, last month.
Asked by French sports daily L'Equipe on Saturday if any other player could have drawn him back to a sport he once hated, Agassi said: "I don't know. Novak inspired me, he gave me the desire to make that effort.
"Many other players have approached me before, I cannot say who. Novak is 30, he won 12 grand slam titles and I know he has the capacity to win many others."
Agassi, who won eight grand slam titles himself, retired in 2006.
The former world number one is in Paris where Djokovic is defending his title, but will leave on holidays with his family next week.
"Novak is a good guy, and he's a chance for this sport. And I can help him. I think he will get better every day," he said.
"It's inspiring to be with him. Sometimes you follow your heart and I think it's the time for me to take care of this guy."
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