Former No. 1 returns as Swiss Fed Cup coach.
The 23-time major champion has not been drawn to play singles on Saturday.
The World No.5 will be replaced by World No.25 Barbora Strycova.
Australian Open champion can regain No. 1 with Rotterdam semifinal run.
One game from victory, Brown went down with a back injury then confronted insults and threats online.
The Spaniard's held the No.1 ranking at the same time last season for a spell.
World No. 2 spotted wearing Swoosh brand in Romania.
