How to clean fresh blood stains off a tatami mat? Need answer fast!

Hi everyone. It all worked out, so no worries. Thanks for all your suggestions, and I’ll talk about my Japan trip in a new thread that I’ll make in a day or two.

Are these two Sherlock Holmes references I see?

Another example showcasing the general lack of info on Wikipedia. This link doesn’t even mention the possibility of staining a tatami mat with blood, let alone how to clean it.