Former champion Rafael Nadal reached the fourth round without lifting his racquet at the $4.33 million BNP Paribas Open on Monday.

The fifth-seeded Nadal was scheduled to meet Leonardo Mayer on Day 5, but the Argentine pulled out of their scheduled third-round match with a back injury on a day when an earthquake shook Southern California.

"I was very scared. First time in my life," Nadal said. "I finish the earthquake, and I was my legs were like this," trembling his legs.

The quake had an estimated magnitude of 4.7 on the Richter scale and the epicenter was about a dozen miles from the desert town of Anza, about 100 miles from Los Angeles.

The former world No. 1 and reigning French Open champion Nadal was the 2007 Indian Wells titlist and 2011 runner-up.

Also on Monday in the California desert, tall South African Kevin Anderson handled Finnish veteran Jarkko Nieminen, 6-3, 6-1.

The 2013 Indian Wells champ will collect $1 million.