The condition of Field Marshal S H F J Manekshaw, who was rushed to the army's Specialised Research and Referral Hospital in Delhi for treatment from Tamil Nadu early on Monday morning, has improved, doctors said.
Ninety-one-year-old Manekshaw was suffering from pneumonia and renal problems but his condition was stable, doctors attending on him said.
He was earlier flown in from his home, Stavka, in Conoor, Tamil Nadu, army sources said.
The sole surviving field marshal in the Indian Army is a veteran of the Burma campaign in World War II. He was decorated with the nation's second highest award, the Padma Vibhushan, after the 1971 Indo-Pak war. He settled down in Wellington in Conoor district in Tamil Nadu after he retired from the army in 1973.
He was admitted to the Military Hospital in Wellington following complaints of breathlessness four days ago.
He was the first Indian Army officer to be appointed Field Marshal in honour of his role in the 1971 war.
Subsequently General K M Cariappa, the first Indian Commander in Chief of the Indian Army, was also conferred the rank of field marshal.