Aaron Cook had to settle for bronze at the World Taekwondo Grand Prix in Manchester.
The Isle of Man fighter was defeated in sudden-death in his semi-final against Russian Albert Gaun on Saturday night.
This was after their fight finished 9-9.
Cook had earlier taken a massive scalp in the quarter-finals when he beat American two-time Olympic champion and five-time world gold medallist Steven Lopez 17-14.
The championship was won by British Olympic bronze medallist Lutalo Muhammad who defeated Guan, also in sudden-death.
Muhammad was selected controversially ahead of Cook for the Olympics last year, prompting him to decide to fight for another nation.