Matthew Sates wins his second medal at the world championships

Rivolta was second in 49.07. Noe Ponti of Switzerland won the other semifinal in the identical 49.07, slower than his heat effort of 48.81. 

Lara van Niekerk twice smashed her 50m breaststroke African mark. 

First she knocked 0.17 off her old record as she posted 29.45 in the heats and then she went 29.27 in the semifinals, finishing third behind favourite Ruta Meilutyte of Lithuania, the winner in a 28.37 world record and American Lilly King in 28.86. 

Sates returns to action on Saturday in the 200m freestyle, while Pieter Coetzé takes aim at the 200m backstroke podium.

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