I scarcely believe this report, and I dearly hope its proven to be completely wrong. But from Team Tachiai contributor Nicola, this heartbreaking post on Instagram

We devoted a 20 minute podcast segment to this terrible incident, and the clumsy reaction from the NSK staff. Now it seems that leaving a critically injured man face down on the dohyo for several minutes while you get a clue can, in fact, be fatal.
I love sumo, but this should be considered a huge loss of face for everyone involved. Yes, people get hurt in sumo – its a combat sport. But that’s why its unthinkable that the world’s greatest sumo institution would not be ready every day, every match for someone to be injured, and be able to respond correctly in an instant.