Nadal had been due to play Ramkumar Ramanathan as the five-times champions seek promotion back to the World Group.
Feliciano Lopez replaces the former world number one who lost to Frenchman Lucas Pouille in the fourth round of the U.S. Open earlier this month.
Nadal is hoping to feature in Sunday's reverse singles against Saketh Myneni at New Delhi's RK Khanna stadium.
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(Reporting by Amlan Chakraborty; Editing by Tony Jimenez)
