Pacific Life Open is a $2.1 million WTA Tour event on hard courts at Indian Wells Tennis Garden in California.
Kuznetsova, seeded second, progressed toward quarter-finals after an easy two-set win over Japan's Ai Sugiyama, while three other highest-ranking players, Maria Sharapova (1), Martina Hingis (3), and Nadia Petrova (4) lost their fourth round matches.
Sharapova, WTA defending champion, was thrown out of the tournament by Russia's Vera Zvonareva following an astonishing upset that saw her losing seven consecutive games after what appeared to be an easy road to victory in the first two sets.
With this defeat, the 19-year-old Russian tennis star will most certainly lose her number one
seed when the updated WTA rankings are issued next week.