Gensan Punch

The film is inspired from the biography of Naozumi Tsuchiyama, a Japanese boxer with a prosthetic leg who went to the Philippines who became known as Gensan.[9] Gensan is also the nickname of General Santos, a city which has produced numerous Filipino boxers including Manny Pacquiao.[7][8][10] Tsuchiyama due to his disability was barred from pursuing a professional career in Japan by authorities due to safety reasons. He went to the Philippines and won a match in 2006 which was instrumental to him obtaining a pro boxing license. He would retire in 2015, without participating in a professional match in Japan.[9]

Mendoza had no prior knowledge of Tsuchiyama.[7] The director went to Tokyo to meet Tsuchiyama and other Japanese boxers and also went to Okinawa, the boxer's hometown.[11] The production team also went to the gymnasium in General Santos where Tsuchiyama trained and talked with the local boxers in the area as part of the production process.[7] Mendoza had an impression that Japanese boxers fight for honor and prestige, a different motivation to their Filipino counterparts.[11]

Mendoza considers his work on Gensan Punch is a deviation from his previous works he has described as "alternative cinema" and considers the film as "mainstream". For Gensan Punch he said he had to tap to his previous experience in the advertising industry where the creative process is "different, if not more rigorous" and considers more about the audience when making media – in contrast to the process in making "alternate films" where the story, rhetoric and philosophy had more weight.[12] The film did not focus on the technicalities of boxing, instead Mendoza decided to highlight Tsuchiyama's "journey as a disabled boxer".[9]

Filming took place both Japan and the Philippines. Filming locations in Japan include Okinawa and Fukuoka.[6] Some scenes in Japan were filmed during the COVID-19 pandemic but scenes involving large crowds were taken prior to the pandemic.[11] Working with Japanese actors, Mendoza used a "non-scripted method" and the boxing bouts had no choreography.[9]