ACAPULCO, Mexico — Rafael Nadal's comeback from a hip injury is on hold after the second-ranked Spaniard pulled out of the Mexican Open, saying he needs more time to recover.

Nadal was forced to retire during the Australian Open quarterfinals and hasn't played since. He was set to play Feliciano Lopez in his opening match on Wednesday but said he felt pain during his final training session on Tuesday.

Nadal said "I think this is less serious than what happened there (in Australia). But there is a risk to make this problem bigger."

The former No. 1 still hopes to be fit to play in Indian Wells and Miami next month.

Nadal won the Acapulco tournament in 2005 and 2013.