Do you know how Mahesh Kale and Rahul Deshpande became friends?

Mahesh Kale and Rahul Deshpande are both veteran singers in Marathi music industry. But have you ever wondered about the story behind their friendship?
In an interview with Maharashtra Times, Rahul Deshpande speaks about his friendship with Mahesh who was his senior. Talking to the daily, Rahul had said, “I used to listen to many of his songs. But I did not know him too well.When Mahesh was in the US, I got in touch with him to ask if he would be keen to take up the role of Sadashiv in Katyar Kaljat Ghusli. That’s when I spoke to him. Once he came back, we became really good friends.”
In the interview, Rahul has also said that he calls Mahesh Beta and the latter calls him Appya.