First to fall was  Jack Sock (USA).  Ivo Karlovic remains a dangerous player even at age 37. With a serve like his, he will remain a threat on the fast courts at least for a few more years. That is probably not what players want to hear, because it is so difficult to break him. It is so frustrating to lose a match in two tiebreaks especially when you were never broken throughout the match. Karlovic won 7-6(4), 7-6(6).
Next to fall was  John Isner (USA), the number one seed.  Steve Johnson (USA) is riding a wave of confidence after winning his first title in June. Isner is a well-known opponent and their matches are always difficult. The last time Johnson beat Isner was in 2014 at this tournament. Four of their five previous matches have included at least one tiebreak set. Tonight was no exception and Johnson won 7-6(7), 7-6(15). Johnson into his second semifinals of the season, with plans to have many more before the year is over.
First two semifinalists are set, who will join them?
Bank of the West Classic, Stanford
 Johanna Konta (GBR) had her hands full with  Saisai Zheng (CHN). In a match where neither player seemed determined to hold serve, there was actually some great points. Konta the number three seed was expected to win and probably struggled under the weight of expectation. In the end, she battled through the nerves with some scrappy tennis to win 6-2, 4-6, 6-3. She is the first one into the semifinals and will await either Dominika Cibulkova or Misaki Doi.