When anti-doping tests were introduced into international chess, Hübner declared his withdrawal from the German national team. He views these tests as bureaucratic power displays that degrade the individual. In his opinion, doping in chess cannot improve the true abilities of a player, only their application. "I am always happy if my opponent's abilities can fully unfold, because then I learn more." Additionally, Hübner is known as one of the world's best xiangqi players not from China.