Neil Robertson suffered a shock 4-2 loss to Lei Peifan in the first round of the Gibraltar Open.
At 17, Lei is making his way in the game but he showed no signs of nerves against the former world champion.
Robertson made a surprising amount of errors and they cost him dear, as Lei advanced to the second round.
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The rot set in early for Robertson, who made a surprise error of judgement when taking on a red that had little value with no way of getting on a colour. He left it in the jaws and Lei was able to step in and take the opening frame.
Robertson hit back to take the second, but the 39-year-old made another mistake when missing a red and seeing it bounce round the table and into the open for Lei to pounce and move back in front.
Lei took the fourth frame to move within one of victory. He had a chance to close out the win in the fifth frame following a Robertson error, but he ran out of position from brown to blue and his Australian opponent took the final colours to keep himself alive.
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Robertson, the world number three, had a chance to force a decider when in the balls in the sixth, but he did not get a great split of the pack and missed a tough recovery red.
Lei blinked in the previous frame, but held himself together superbly with a match-clinching break of 56.
Robertson made him sweat by coming back to the table requiring five snookers. He got one and closed the gap courtesy of a free ball, but Lei got his chance and knocked in the colours to secure the win and a meeting with Dylan Emery who beat Ben Hancorn 4-0.
Thepchaiya Un-Nooh was not at his best, but he still had too much table craft to claim a 4-0 win over Sean Maddocks.
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