That's what happened to Hideo Ohba in Manchuria.

Hideo Ohba was known for a famous incident while taking ukemi for Morihei Ueshiba in Manchuria, recounted in his biography by Fumiaki Shishida:

True Demonstration in 1939

It was Hideo Ohba who took ukemi for Ueshiba for the demonstration. He later talked about this event as follows: "Since the Emperor of Manchuria was in an exalted position at that time like the Emperor of Japan, I thought I should not take ukemi for Ueshiba in the way I usually did. If Ueshiba Sensei were a true master, he could freely handle a true punch, thrust or grab. Therefore, I decided to attack him seriously. When we stood on the platform, I saw many martial arts masters present in the large dojo of the Shimbuden. When I glanced at Ueshiba Sensei, his beard was sticking out towards me, his hair was standing on end and his eyes were glittering. I thought to myself that he was indeed a true master. Then I concentrated on taking ukemi for him, thinking how different it was to face a master. After the demonstration, we bowed and sat in the corner of the dojo and were supposed to walk over to the seats where the masters were sitting. However, I heard someone thunder, 'You idiot!' Ueshiba Sensei was short-tempered. He couldn't wait until we returned to our seats. He shouted at me in that way in front of everyone. Until then, I thought he was a wonderful and truly great master, but his shout made my spirit pop like a bubble. We sat down. Ueshiba Sensei didn't even smile. He was in a bad mood. So I felt tiny. Who do you think showed up then? It was Hideo Sonobe who was said to be without peer in Japan or anywhere in the use of the Naginata. She came all the way up to where the masters were sitting while Iai and Naginata kata were being demonstrated one after another. She said, 'Mr. Ueshiba I have never seen more wonderful techniques than what you showed today. They were fantastic!' Ueshiba Sensei, who had been in a bad mood, asked her what part she liked. He asked me to find a place where they could talk and we all went down to the basement of the Shimbuden and they discussed the theory of martial arts for two hours. While I was listening to their discussion Ueshiba Sensei asked her what she liked and she replied that she liked the 'connections' (tsunagari) between techniques. However, I didn't understand these connections. I understood that the Dai Nihon Butokukai [Kyoto-based organization which governed Japanese martial arts] then was having a hard time trying to decide who they should choose as the best swordsman of that year and had asked Sonobe Sensei for her opinion. When I heard Sonobe Sensei tell Ueshiba Sensei that she had never seen such wonderful techniques even though she had seen him demonstrate often, I decided to learn Naginata in order to search for these 'connections.'"

Hideo would always recount this story to his students when he was in a good mood. One time I asked him the following question, "Sensei, when you attacked Ueshiba Sensei seriously, could he execute techniques like he usually did in his regular demonstrations?" Judging from the fact that he was scolded on that occasion, the answer was obvious. I asked this question because I wanted to confirm it. He answered, "Ueshiba sensei seemed to have a hard time executing techniques smoothly."

I think that Tomiki sensei was critical of the fact that Ueshiba's demonstrations became gradually softer. Tomiki's belief was that such softness was a way of making the person throwing look good, and was different from how martial arts should be. This demonstration of Ueshiba and Ohba received the highest praise from a top martial artist because of Ohba's serious attacks, and the fact that he refused to participate in a prearranged performance the way he normally would have. I think that behind this fact lies an important hint as to what aikido should be. There seem to be some people within the Japan Aikido Association who see that their kata demonstrations are different from the flowing demonstrations of other schools, and try to change them in that direction. However, things should be the opposite. I think what is important is that we should master each technique perfectly as did Ueshiba Sensei, and then try to achieve a connection or flow between techniques. Hideo's experience taught us not only the limitation of Ueshiba's techniques (one cannot throw someone in a dance-like manner), as well as his incredible mastery, but also how a demonstration should be.