Rihanna performs during a stop on her "Last Girl on Earth" tour at Staples Center in Los Angeles

Rihanna, top, performs during a stop on her "Last Girl on Earth" tour at Staples Center in Los Angeles, Wednesday, July 21, 2010

Rihanna performs during a stop on her "Last Girl on Earth" tour at Staples Center in Los Angeles, Wednesday, July 21, 2010. (AP Photo/Chris Pizzello

Rihanna Last Girl on Earth Tour 2010 Part 1

Rihanna Last Girl on Earth Tour 2010 Part 2

Rihanna - Last Girl On Earth Tour Rehearsal Part 1

Rihanna - Last Girl On Earth Tour Rehearsal Part 2