World number one, Serena Williams, has withdrawn from the BNP Paribas Open in Indian Wells and the Miami Open, due to a left knee injury.
Serena will now relinquish the world number one tennis ranking to German, Angelique Kerber.
The two-time champion at the showpiece event at the California desert resort, had returned to the women’s top ranking in January after claiming a record 23rd grand slam singles title in the professional era at the Australian Open.
The 35 year old had needed to reach the Indian Wells semi-finals for a chance to retain her number one ranking.
