By James Goyder

Reigning IBF flyweight champion Amnat Ruenroeng rematched Johnriel Casimero in Beijing this evening (local time) and the Filipino stunned the Thai with a devastating fourth round KO.

The fight looked evenly poised going into the fourth round and Ruenroeng attempted to pick up the pace and land a quick combination. Casimero read his intentions and countered with a thunderous left hook that put Ruenroeng on the canvass for only the second time in his professional career.

The former Olympian was badly hurt and barely beat the count. Casimero swarmed all over him as Ruenroeng, who is normally known for his evasive footwork, became a completely stationary target and tried to block punches with his hands and arms.

The Thai was able to buy himself a bit of time but Casimero was relentless and with Ruenroeng holding his hands high and leaving his midsection wide open he finished off a combination with a brutal left hook to the liver. This time there was no question of the champion recovering as the referee waved off the fight with the 36 year old in obvious agony.

There had been no indication in the opening three rounds of the drama which was to follow. The first three minutes of the fight were almost entirely uneventful as Ruenroeng seized the middle of the ring and Casemiro circled around him with both fighters reluctant to commit to combinations.

In the second stanza the pace picked up as Ruenroeng clipped Casemiro with a left hook upstairs and the Filipino answered with a left hand to the body. The Filipino landed a couple of right hands to the head towards the end of the round as the champion answered with a right hook left jab combination.

In the third round Ruenroeng continued to jab to the body and head and thought he had a knockdown when a left hook sent Casemiro stumbling to the canvass. The referee ruled it a slip and he had some strong words for the Thai at the start of the fourth after he fell into the challenger, blaming an untied shoe lace.

After the foul filled first fight between these two fans might have been fearing the worst but moments later Casemiro would end the contest in the most decisive of manners. The loss is Ruenroeng's first and sees his record drop to 11-1 while The Filipino improves to 23-3 and is the new IBF 112 lbs champion.