Calcutta: Former India footballer and coach Amal Dutta passed away on Sunday evening. He was 86 and is survived by wife, son and daughter.

Dutta was suffering from Alzheimer's for nearly three months and was bedridden.

"His condition was getting from bad to worse since morning. He had a massive respiratory trouble in the afternoon. He breathed his last around 8.10 pm," Dutta's son Ashish said.

Dutta introduced the 'diamond system' to Indian football in 1997. He was also known as someone who spoke his mind, not bothering much to mince his words.

A midfielder, representing India at the 1954 Asian Games apart from playing for both East Bengal and Mohun Bagan, Dutta later made a name for himself as a tactical genius as he pioneered professional coaching in India.

Dutta had also gone to England for a one-year FA coaching course. He was always very enthusiastic about modern football.

He became the technical director of the Indian team for the Nehru Cup in 1988. Under his guidance, India had gone on to win the SAF Games in 1987.

In a condolence message, Chief Minister Mamata Banerjee wrote on her Twitter handle: "Saddened at the passing away of Amal Dutta. Football world will miss him. It's a great loss. My condolences to his family and friends."

Later on, the chief minister also spoke to Dutta's son. "He was a true fighter and fought till the end," said the legendary PK Banerjee. "He was like a family member... I am really not in a position to talk further at this point in time," Banerjee said.

Another former India captain Chuni Goswami also conveyed his condolences. "It's a very sad news. He introduced modern football technique to our country," said Goswami.

"I don't know what to say. May his soul rest in peace," former India footballer Shyam Thapa said.

Jose Ramirez Barreto too couldn't hide his sorrow after coming to know of Dutta's demise. "It's a very sad news. He was really a very good coach," Barreto said.

Dipendu Biswas, the former India footballer who played under Dutta's coaching in 1997, got emotional while speaking about his Amal sir.

"He was an institution. I have learnt a lot, thanks to him," Biswas said.

State sports minister Aroop Biswas and MoS sports Laxmi Ratan Shukla also reached Dutta's house to pay their last respect.

"Dutta's body will be kept at Rabindra Sadan from 10 am to 2 pm on Monday.

"Chief Minister will pay her homage to Dutta around 11.30 am," Biswas said.