The former world No 1 became just the third woman, after Kim Clijsters and Steffi Graf, to win in Indian Wells and Miami back-to-back.
Australian Open champion Angelique Kerber retakes second spot from Agnieszka Radwanska thanks to her run to the semi-finals, where she lost to Belarusian Azarenka.
Serena Williams still holds a substantial lead at the top, despite losing to Kuznetsova in the last 16, her first defeat at the tournament since 2012.
Two-time major winner Kuznetsova is the biggest mover in the top 20, leaping six places to 13th.
