As the boy was making a move during the match last week in the Russian capital, the robot grabbed his finger so hard it broke it, confirmed President of the Moscow Chess Federation, Sergey Lazarev.
He told Russian state-owned news agency, TASS: "This, of course, is bad.
"The robot was rented by us, it has been exhibited in many places for a long time with specialists...
"The child made a move and after that we need to give time for the robot to answer, but the boy hurried - the robot grabbed him. We have nothing to do with the robot."
Footage, uploaded by Baza Telegram channel, shows people rushing to help free the boy's finger from the robot
Video footage of what is claimed to be the incident, uploaded by Baza on its Telegram channel, shows the robotic arm wait as the boy decides what move he is going to play.
The arm, which has a hand-like gripping tool at the end, appears to grab the boy's finger and hold on as the boy is seen struggling to wriggle free. Assistants and others watching rush to his aid to help free the robot's grip.
Mr Lazarev told TASS the boy finished the game the following day in a cast but his parents want action to be taken against the federation.
"The child played the very next day, finished the tournament in a cast, and the volunteers helped to record the moves," he said.
He said his organisation had been contacted by Moskomsport - the Department of Sport for the Russian capital - informing him the boy's parents want to contact the public prosecutor over the incident.
Mr Lazarev vowed the chess federation will help the boy's family "in any way we can" and the robot operators will have to look at "strengthening protection so that this situation does not happen again".
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