"I was sick two days, so I couldn't practice for two days," he said at a pre-event press conference.
Rafael Nadal, who came in having reached the final of Acapulco a week ago, said he had begun practicing the first day of the men's singles event and also played a first-round match in doubles.
He indicated the illness had been draining, but added, " I hope to recover myself good and feel myself ready to compete at the highest level possible."
The Spaniard would not comment on his quarter of the draw, which includes Roger Federer, Novak Djokovic, and a potential third-round meetup with Fernando Verdasco.
" I know I am playing with Guillermo Garcia or Guido Pella first round, and that's all that I can say now," he said. " If things go well, we will have time to talk about the draw."
Nadal is a three-time Indian Wells champion. He received a Bye in the first round and will be playing Guido Pella in the second.
