On day 8 of the Australian Open, all eyes were on Serena Williams vs. Simona Halep, and the match did not disappoint. On The Tennis Podcast, David Law and Catherine Whitaker are full of praise for both players.Was that the best Serena has played since returning from giving birth? How was she able to wrestle control in the decider? And has being without a coach actually helped to liberate Halep this tournament?Alexander Zverev, on the other hand, played very badly in a straight-sets defeat to Milos Raonic. Why can’t Zverev step up at Grand Slams? What has happened to his serve? Does he have an attitude problem? And how long will Ivan Lendl stick around if this keeps happening?Elsewhere, Novak Djokovic beat Daniil Medvedev, but not without a few problems. Are there some vulnerabilities in the World No.1's game?Finally, David and Catherine discuss impressive wins for Naomi Osaka and Lucas Pouille. And what caused Pablo Carreño Busta to lose his temper with the umpire after losing a five-setter to Kei Nishikori?The Tennis Podcast will be produced daily throughout the Australian Open (and at all the Slams) after our Kickstarter was funded by our listeners. It is produced in association with The Telegraph. See acast.com/privacy for privacy and opt-out information.