Rafael Nadal was forced to pull out of Spain's Davis Cup World Group play-off with India on Friday due to a bout of gastroenteritis.
The world number four had been pencilled in to open Spain's quest to return to the World Group in 2017 against Ramkumar Ramanathan in Delhi.
However, the 14-time grand slam champion was replaced by Feliciano Lopez, with Spanish captain Conchita Martinez hopeful Nadal will be fit to play in the reverse singles on Sunday.
In his absence Lopez made a promising start to the opening match of the tie, the 34-year-old taking the first two sets against Ramanathan.
Spain have won the Davis Cup five times since the turn of the century, but have not appeared in the World Group since 2014.