STANFORD, CA - JULY 21: Catherine Bellis of the United States reacts after winning her match against Sachia Vickery of the United States during day four of the Bank of the West Classic at the Stanford University Taube Family Tennis Stadium on July 21, 2016 in Stanford, California. (Photo by Lachlan Cunningham/Getty Images)

STANFORD, CA - JULY 21: Catherine Bellis of the United States reacts after winning her match against Sachia Vickery of the United States during day four of the Bank of the West Classic at the Stanford University Taube Family Tennis Stadium on July 21, 2016 in Stanford, California. (Photo by Lachlan Cunningham/Getty Images)