Pic: Tai Chengzhe / TOP147.com
World No 1 Selby was badly out of sorts as he suffered his second consecutive defeat in the first round of a ranking event - though he did win the Paul Hunter Classic PTC event last month. Cope, who reached the final of the China Open back in 2007, goes through to the last 16 to meet Stuart Bingham or Tom Ford.
Stoke's Cope won the opening frame before Selby, who beat Mark Williams 10-9 in the final here last year, levelled with a break of 49. Cope cleared from green to black to take the third frame then added the fourth by potting a mid-range final black after Selby's attempted thin cut failed to find a baulk corner.
The fifth frame also came down to the colours and Selby was unlucky to narrowly miss a long yellow to a top corner after his opponent had gone in-off when escaping a snooker. Cope cleared up for a 4-1 lead, then finished in style with a 71 in the next.
"It wasn't an enjoyable match because the standard was not great," admitted Cope, who slipped 12 places to No 27 in the world last season after a string of poor results. "I won a few close frames which could have gone either way and that was the difference."
Selby said: "It's disappointing to come here as defending champion and not have a run. I played poorly and Jamie picked up the pieces. I had more than enough chances but couldn't take them. I have struggled this season other than winning the Paul Hunter Classic.
"My sleep pattern has not been great, which happens sometimes when we come here. I have tried different solutions but that's just the way it is. Sometimes you wake up at 2am and can't get back to sleep so you go for a practice."
Stephen Maguire gained a measure of revenge for last season's China Open final by beating Peter Ebdon 5-3. Maguire trailed 3-2 but made breaks of 73 and 58 to lead 4-3. The next frame lasted 75 minutes as Ebdon battled for the snooker he needed on the colours, until he accidentally potted the pink to bring an end to the match.
"It was rubbish, the two of us bogged each other down," said Maguire. "It wasn't a good match to be involved in but at least I've got time on the practice table now to prepare for my next match."
There were two wins for the Chinese wild cards as Jin Long edged out Jimmy Robertson 5-4 and Chen Feilong saw off Fergal O'Brien 5-2 with top breaks of 52, 59 and 55.
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