Bumrah said Rohit backed him to bowl the most important overs even when he was new at MI.
According to Bumrah, Rohit has played an instrumental role in his development as one of the world's premier fast bowlers.
"When I came into the side Ricky (Ponting) was the captain and I was not playing regularly. I started playing a lot under Rohit, he had a lot of confidence in me. He instilled a lot of confidence," Bumrah said during a conversation with Ravichandran Ashwin on his YouTube show DRS With Ash.
"He (Rohit) saw me bowling at nets, he saw what kind of skills that I have so he always backed me and always told me to believe in myself and in the initial stages as well he had a lot of trust in me, so he will give me the important overs.
"That tells me that okay I can do the job, sometimes you are still trying to convince that okay maybe it is the right call that I am doing the tough job, but they have put you into the tough zone so then you will find a way how to come out of it. The relation has been same."
Both Rohit and Bumrah have been a constant factor in Mumbai’s success in the IPL over the years.
Speaking further on Rohit, Bumrah said: "He has a lot of trust in me till date and so now we have reached a point where he doesn't even tell me what do you want to do. He says 'you set the field on your own and if there are any changes you tell me and I will do that'".
"That amount of trust has happened. He has had that trust because he has followed whatever I have said, asked for a field and that has worked so the relationship has really developed.
Rohit is known for his calm demeanour and leads the team by example, something that has impressed Bumrah.
"It's always very chill, some days things might not go well but he always has kept the atmosphere in our team very simple, and he has always tried to keep it very calm. All these things have really helped me as a cricketer, maybe not get overawed.
"He has a lot of trust and that is always the best place for me as a bowler because, then, I have got the freedom to do whatever I want to. That is really beneficial for me as a bowler and it's very important for me going further."
(With PTI inputs)