Glamorgan secured a place in the semi-finals of the Yorkshire Bank 40 courtesy of a four-wicket triumph over Yorkshire Vikings at Headingley.
Captained by Richard Pyrah in the absence of Andrew Gale, Yorkshire’s young side gave a good account of themselves but Glamorgan's batsmen always had a 216 target well within their sights.
They were in some trouble when openers Gareth Rees and Mark Wallace soon departed to the new-ball pairing of Iain Wardlaw and Moin Ashraf.
However, the in-form Chris Cooke revived the innings with a brisk 84 from 78 deliveries and Graham Wagg’s late firepower ultimately proved decisive.
With 31 required from four overs, Wagg tore into Pyrah with three sixes in the space of four deliveries and, although he subsequently fell for a 17-ball 31, Glamorgan made it home with seven balls unused to qualify as the competition's best runner-up.
Yorkshire made a dreadful start after winning the toss but were rescued by a century partnership between Dan Hodgson and New Zealand batsman Kane Williamson.
Dismissed first ball on his LV= County Championship debut against Nottinghamshire at Trent Bridge last week, Williamson tuned up well for Wednesday's vital top-of-the-table clash with Durham at Scarborough with a cleanly struck 45 off 69 balls, including two fours and two sixes.
Hodgson continued to bat with great composure after his Kiwi partner had gone and looked set for his maiden White Rose century until he was caught at backward point off Wagg for a career-best 90 from 98 deliveries.
Yorkshire's final score of 215 for five still looked some way below par, despite late runs from Adam Lyth and Leaning, but was far more than seemed likely early on, when teenage debutant Jonathan Tattersall was bowled for a duck and Alex Lees was run out for two.