A JapanBall video analysis of Kazuma Okamoto (and some comparison with Munetaka Murakami):
https://www.youtube.com/watch?v=fMZBoO_96Z4
Another Okamoto video analysis:
https://www.youtube.com/watch?v=kOC0oxgph1k&t=1014s
... and at 6:45:
https://www.youtube.com/watch?v=WzPdyiMExck