
Sawant's demise came to light when he did not report for the training session in morning and so other team staff went to his room, Police said.
"When there was no response after knocking the door repeatedly, the room was opened and they (the staff members) found him lying unconscious," police said.
Marine Drive Police was informed and Sawant was immediately shifted to Bombay Hospital where he was declared dead before admission.
It is suspected that he may have died due to cardiac arrest, they added.
The exact reason of his death will be ascertained only after post-mortem, Deputy Commissioner of Police Manojkumar Sharma said.
BCCI in statement condoled his demise.
"BCCI regrets to inform that India Under-19 strength and conditioning trainer Rajesh Sawant passed away, in his sleep, in Mumbai, on Sunday morning. Sawant was on national duty with the India Under-19 team preparing for the series against the touring England Under-19 team," the Board said in statement.
"Sawant, 45, is survived by his wife and daughter," it said.
"On behalf of the BCCI, I convey my heartfelt condolences to the bereaved family and our prayers are with them, to overcome this irreparable loss," BCCI Joint Secretary Amitabh Chaudhary said in the statement.
The India team is scheduled to play five 50-over games and two four-day games against England Under-19 from January 30 at Wankhede Stadium.
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