The Brit was a break ahead in the deciding set when home favourite Zhang Zhizhen called it a day at 6-3 6-7(3) 4-2.
Murray, still ranked above his wildcard opponent despite languishing at 311 in the world, was forced the distance after losing a second set tie-break. He will face David Goffin in the next round.
The three-time Grand Slam champion, who marked his arrival in China by accidentally smashing a commemorative plate during a photo opportunity, has said he will end his season after playing tournaments in Shenzhen and Beijing.
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Murray, who bowed out in the second round at the US Open to Spain's Fernando Verdasco, hopes that curtailing his season will help him return stronger for the 2019 Australian Open in January.
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