Venus Williams has withdrawn from next week's Qatar Open due to an ongoing lower back injury.
The 23rd-ranked Williams has been hampered by back problems since the Australian Open. She missed the Open GDF Suez tournament and will skip the upcoming Fed Cup match against Italy because of the injury.
Andrea Hlavackova will replace Williams in the Qatar tournament.
Williams lost in straight sets to Maria Sharapova in the third round of the Australian Open, and then lost in the quarterfinals of the doubles alongside younger sister Serena.
Serena Williams, who complained of back pain during her Australian Open quarterfinals loss to American Sloane Stephens, is scheduled to play at Qatar, as is top-ranked Victoria Azarenka.