Defending champion Anthony Keenan crashed out of the Harold Ryden Championship last night at the hands of Nelson's Craig Waddington.
The 2018 winner from Burnley was beaten 3&2 at Blackburn as his bid to retain the trophy ended at the quarter-final stage.
Three former champions, Gary Blades, Nick Uttley and Anthony Harwood, all booked their place in the last four with comfortable wins.
Blades, winner in 2008, was too good for Curtis Clarkin and won 5&3 while Uttley recovered from a shaky start to see off Mark Ridgway 4&2 and Harwood defeated Pleasington's Owen Leigh 3&1.
Waddington's reward for beating the reigning champion is a clash with his Nelson club-mate Uttley tonight in the first semi-final while Blades and home favourite Harwood meet in the second.
It was all going to plan for Keenan, who beat Carl Parker in the final a year ago, as he birdied the par-five fourth to move one up and stayed ahead until the ninth.
However, a lost ball on the 10th and a penalty drop on the 11th cost him dearly and with his opponent winning the 13th and 14th the game was quickly getting away from him.
When both players made par on the 16th time was up for two-handicapper Keenan.
2002 champion Uttley was two down after nine holes against Ridgway but gathered himself together to clinch victory in what was the first of three Nelson v Burnley games last night.
After being handed a two-up lead on the 14th by a poor three-putt, he made no mistakes over the next two holes to book a semi-final spot on the course he won at 17 years ago.
It is 11 years since Blades' triumph in the Harold Ryden but he gave an ominous warning to the other three left in the competition last night with a comprehensive win over former runner-up Clarkin.
The Burnley member was two down after five but turned the game on its head with three birdies at on the trot from the ninth.
A further birdie three on the 15th closed out a 5&3 win.
After Saturday's 36-hole qualifier all hope of a home win lay on the shoulders of Harwood and he kept the dream alive for his club.
After nine holes he was level with young Pleasington opponent Leigh as both went out in one over par.
Birdies at the 10th and 12th proved crucial, though, and a closing bogey on the 17th was enough to ensure the 2017 winner progressed into the last four.
Semi-final draw - Tonight, June 25
5.15pm: Nick Uttley (Nelson) v Craig Waddington (Nelson)
5.30pm: Gary Blades (Burnley) v Anthony Harwood (Blackburn)
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