Pourshab had failed to book a place in the final match of the Kumite −84 kg after losing to Valerii Chobotar from Ukraine.
The gold medal went to Croatian Ivan Kvesić who defeated Chobotar in the final.
The 24th Karate World Championships are Karate's biggest event. Held every two years, the Karate Senior World Championships gather athletes from over a hundred countries in a thrilling quest to sports greatness.
The tournament takes place at the WiZink Center sports hall in Madrid, Spain.
The competition acquires even greater importance since the Spanish capital hosts the last World Championships to be held before Karate's debut at the Olympic Games Tokyo 2020.
The championships are the competition providing the highest number of points for athletes to qualify for the Olympic Games.