Veteran potter Mike Dunn claimed the biggest win of his life as he stunned world number two Mark Selby to reach the China Open semi-finals.

The 42-year-old, ranked a lowly 73rd, beat Selby 5-3 in Beijing and will tackle home favourite Ding Junhui on Saturday for a place in the tournament's showpiece match.

Journeyman Dunn thought about quitting the professional tour last season, so despondent was he to be consistently losing in the first round at low-profile events or in qualifying tournaments week after week.

But victory over Selby and a first ranking event semi-final of his 23-year career provide the justification for his taking another crack at the sport.

Before the match, Dunn had said that he would not be worried if Selby thrashed him 5-0, given he was delighted to have already come so far. But now he can start dreaming about a major title.

Dunn is guaranteed prize money of £21,000, however the champion goes home with £85,000.

Ding will start their match a strong favourite, yet the same was true of Selby on Friday.

China's leading player is aiming to become the first player since Stephen Hendry to win five ranking titles in a season. Having already collected four in the current campaign, Ding has a first-class opportunity now after beating Mark King 5-2, with four breaks above 50 guiding him past the Essex potter.

World number one Neil Robertson and Ali Carter will go head to head in the semi-final on the opposite side of the draw.

Australian Robertson fended off Scotland's Graeme Dott 5-3 in their quarter-final, while Carter came through by the same scoreline against fellow English potter Ricky Walden.

Carter, who faced a battle with testicular cancer earlier this season, is looking to head to the Crucible for the World Championship later this month with a trophy under his arm.

"The World Championship is just around the corner but this is a big event in Beijing and one I enjoy playing in. It's a chance this week to do well at the end of a tough season. I'm giving it my all," Carter told World Snooker's website.

"Neil will be tough to beat but it's just great to be in the semi-finals."

Robertson has been troubled by a virus for much of the week, winning three matches 5-4 before being grateful to avoid a decider against Dott.

Until recently, Robertson had looked on course to reach 100 century breaks this season, having long since broken the record for most tons in a campaign, but he has yet to breach three figures in China and is stuck on 92.

He no longer fancies reaching the landmark, saying: "I always try to make centuries but I still need to make eight so it's probably against me now. I'd need to do something amazing in the rest of this tournament and at Sheffield. I'm not really thinking about it any more."