Serena pulls out of Indian Wells

Serena Williams withdrew from the BNP Paribas Open because of a left knee injury, leaving the desert tournament without the world’s top-ranked women’s player.

The withdrawal also cost Serena a chance to retain her top ranking. Angelique Kerber, a two-time semifinalist and now the highest-seeded woman in the event, will supplant Serena at No. 1 after Indian Wells. Williams needed to reach the semifinals to retain the top spot.