Daria Kasatkina of Russia celebrates after winning a game during the second set of her semifinals match against Venus Williams of United States during Day 12 of BNP Paribas Open on March 16, 2018 in Indian Wells, California.

Daria Kasatkina of Russia celebrates after winning the second set of her semifinals match against Venus Williams of United States during Day 12 of BNP Paribas Open on March 16, 2018 in Indian Wells, California.

Venus Williams of United States reacts during her semifinals match against Daria Kasatkina of Russia during Day 12 of BNP Paribas Open on March 16, 2018 in Indian Wells, California.

Daria Kasatkina of Russia celebrates match point against Venus Williams of the United States at the BNP Paribas Open - Day 12 on March 16, 2018 in Indian Wells, California.

Daria Kasatkina of Russia reacts to her quarterfinal victry over Venus Williams of the United States during the BNP Paribas Open at the Indian Wells Tennis Garden on March 16, 2018 in Indian Wells, California.

Daria Kasatkina of Russia celebrates a quarterfinal victry over Venus Williams of the United States during the BNP Paribas Open at the Indian Wells Tennis Garden on March 16, 2018 in Indian Wells, California.

Philipp Kohlschreiber of Germany serves against Juan Martin Del Porto of Argentina during Day 12 of BNP Paribas Open on March 16, 2018 in Indian Wells, California.

Juan Martin Del Porto of Argentina celebrates after defeating Philipp Kohlschreiber of Germany during Day 12 of BNP Paribas Open on March 16, 2018 in Indian Wells, California.

Juan Martin Del Potro of Argentina reacts to match point over Philipp Kohlschreiber of Germany during the BNP Paribas Open at the Indian Wells Tennis Garden on March 16, 2018 in Indian Wells, California.