With a single double-fault, Serena Williams handed Karolina Pliskova a passage through to her first Grand Slam final, the World No.1 ranking to Angelique Kerber, and dashed her own chances of going ahead of Steffi Graf in the all-time list of Grand Slam title holders. Afterwards, David Law (BBC 5 Live) and Catherine Whitaker (Eurosport) got together on the daily US Open Telegraph Tennis Podcast to discuss a couple of hours that shifted the tennis world on its axis.  Where was the Williams-Pliskova match won and lost? What caused Williams to double-fault at match point? Could her nerve be going? How big a factor was the knee injury that she revealed afterwards. Was it poor form to mention it? All discussed on the Tennis Podcast, as well as an assessment of the rise of Kerber, and a preview and predictions of the men’s semifinals. The Tennis Podcast is produced in association with Telegraph Sport. See acast.com/privacy for privacy and opt-out information.