The two men famously fought in 2018. Tenshin won by decision but the fight was in Tokyo, the judges were Japanese and most neutrals felt that the Thai had done more than enough to win.
Both men have talked about wanting to rematch but with Tenshin set to retire from kickboxing after his bout with Takeru in June that most definitely won’t be happening. If they can’t be foes inside the ring then Rodtang doesn’t see any reason why they shouldn’t be training partners!
Whether anyone will translate Rodtang’s invitation for Tenshin, who presumably doesn’t speak great Thai, remains to be seen. But if two of the best stand up fighters on the planet do decide to train together they could probably put the sparring footage on pay per view!