Hi Mike, prior to Saenchai's first fight in the UK I had a discussion with a very senior Thai official in Bangkok regarding this kick, knowing Saenchai would likely throw the kick and that the crowd here would probably like to see it and almost expect it.

As Darren says above, the kick is illegal if Saenchai puts his hands on the canvas and kicks (which he generally does). The Thai official I spoke to was well aware of Saenchai using this kick in fights, He said it was an old Muay Thai technique and eluded to it being spectacular but generally not very effective.

I asked him what his advice would be to referees here. He said that he would not advise referees to penalise Saenchai with a point deduction for the kick as it is not really dangerous, but instead inform him beforehand if his kick was caught during its execution, that his opponent could kick him legitimately irrespective of whether Saenchai's hands were still on the canvas or not. If this resulted in Saenchai being Ko'd, his opponent would win. However, if he Ko'd his opponent with the kick, he would lose by disqualification. That is what we did. In the first fight Liam also did the same kick but neither boxer was hurt.

Saenchai has attempted the kick in Thailand (some time ago now) and there was a debate over the legality of the technique afterwards given it was a traditional technique. It was judged illegal if his hands were on the canvas.