The 26th seed, who fought back from 2-4 to lead 5-4, lost to the 2004 UK champion Maguire on Monday, media reported. (Agencies)
Liang potted 15 reds with blacks in the last frame of the opening match but left himself a difficult cut on the yellow, leaving it at the jaws. A bumper bonus of 55,000 pounds plus the 4,000 high break prize is available for a maximum at the York Barbican Centre.
Fellow Chinese Tian Pengfei also squandered a 3-1 lead against defending champion Mark Selby and was beaten by 3-6 in the second round.
"I didn't start well again. It seems to be the same old story from me. To be fair to Tian, he put me under pressure pretty much throughout the match. The problem is I probably try too hard to get off to a good start and it probably works out the other way instead of going out and relaxing," said Selby.
China's Xiao Guodong fell to former World No 1 Judd Trump 2-6.
The 26th seed, who fought back from 2-4 to lead 5-4, lost to the 2004 UK champion Maguire on Monday, media reported.