Serena Williams has withdrawn from the Miami Open due to a left knee injury.
The eight-time champion was forced to hand a walkover to China’s Wang Qiang in the third round of the tournament.
It's the second consecutive WTA event the 37-year-old Serena has had to withdraw from.
She recently retired from the tournament in Indian Wells due to a viral illness.
Serena is yet to win a title since returning from maternity leave last year.

Leeds thrash Newcastle to climb to third in Premier League
Shabab Al Ahli beat Tractor in AFC Champions League Elite opener
Saudi Super Cup heads to Kuwait in expansion drive
Zverev beats Shelton to win US Open title
VAR got goal award wrong in Manchester derby, says ref's body
