Forecast: Stan Wawrinka will beat Alexei Popyrin. Arguments: Wawrinka won confidently in the first match against Koval, showing excellent gameplay both in serving and receiving. Popyrin, on the other hand, has a series of defeats on clay and shows inconsistent results. Additionally, Wawrinka was one of the best clay court players in the past, which may help him secure a victory. Therefore, I believe Wawrinka will be ready for a rematch and will be able to defeat Popyrin.