Top contenders Karsten Warholm, Rai Benjamin and Alison dos Santos made no mistakes to advance into the Olympic 400 metres hurdles final which promises to be another epic in Paris on Friday. Triple world champion Warholm of Norway was pushed to a world record 45.94 seconds by American Benjamin and Brazil’s Dos Santos at Tokyo 2020. The trio has posted the 17 fastest times in history over the distance, and Benjamin is this season’s leader ahead of 2022 world champion Dos Santos and Warholm in his bid for a big title at last. In the semi-finals at the Stade de France, Warholm clocked 47.67, Benj…