Novak Djokovic
Novak Djokovic of Serbia cools off with an ice towel during a break in play against Kei Nishikori of Japan in their semi-final match at the 2014 U.S. Open.Reuters

World No. 1 Novak Djokovic has finally decided to opt out of the Davis Cup World Group play-off against India, according to Serbian team's non-playing captain Bogdan Obradovic.

Obradovic has also predicted a "tough" challenge against India in the Davis Cup that is scheduled to be held from 12-14 September in Bangalore.

The visiting team's captain said that the main reason Djokovic chose against travelling to the subcontinent for the tie is fatigue.

"Novak is definitely not coming to India, mainly because of fatigue and also he would like to be with his wife who is expecting their first child," said Obradovic on Monday afternoon.

Obradovic also pointed out the harsh conditions in Bangalore that are the contributing factors to Djokovic's decision.

"Novak had a very hard part of the season and he needs a break, a trip to India requires a huge effort, not only in terms of travel, coming from one end of the planet to the other, from New York to Bangalore, but also to the harsh conditions of the game here, high humidity and high altitude" Obradovic added.

The reigning Wimbledon champion suffered a shocking 6-4, 1-6, 7-6 (7-4), 6-3 loss against Japan's Kei Nishikori in the US Open semifinal on Saturday. Djokovic said after the defeat that he is unsure about the tie.

"I would have to speak with my captain and see, see if I'm going to go in India or not. I still don't know," he said.

Djokovic is most likely to be replaced by world No. 179 Ilija Bozoljac, who is already in Bangalore along with his teammates Dusan Lajovic and Philip Krajinovic.

Meanwhile, Obradovic admitted that it would be a tough match against India without their best player, Djokovic. He also stated that his players were confident about their win as they have been in the World Group for eight years.

"I think this is going to be a tough match for both teams. The conditions are tough - the humidity is high, the sun is out and there is a lot of wind as well. Even without Novak, we have a good team and we are high on confidence," Obradovic said.

"We lost a difficult match against Switzerland without Djokovic and Janko Tipsarevic but still we are confident. Dusan Lajovic and Filip Krajinovic are improving a lot and Nenad Zimonjic is an experienced guy to have for doubles.

"Someone like (reserve) Ilija Bozoljac plays well with him and they showed that by beating the (World No.1 pair) Bryan Brothers (of the United States) last year," the captain said.