Derbyshire reached Finals Day for the first time after beating Gloucestershire by seven wickets.
Wayne Madsen struck 47 as the Falcons picked up a fourth-consecutive win in the Vitality Blast, with Derbyshire chasing down 136 with 17 balls to spare.
The opening partnership of Miles Hammond and Michael Klinger started well and put on 44 runs before Fynn Hudson-Prentice (2-26) struck for the Falcons, having the former caught by Alex Hughes for 31.
Klinger topped the run-scoring charts for Gloucestershire heading into the quarter-final, but he was only able to add 15 to his tally before being run out by Ravi Rampaul.
Hughes conceded just 19 runs from his four overs and claimed one wicket, while Matt Critchley continued his good form with the ball to take 2-21.
Rampaul dismissed Andrew Tye (6) in the final over to claim his 22nd wicket of the competition, the most by any player this year as Gloucestershire posted a total of 135-7 from their 20 overs, with Ian Cockbain unbeaten on 45.
Luis Reece (15) and Billy Godleman (25) made a quick start in reply as Derbyshire whittled away at the total, with a maiden Finals Day appearance in prospect.
After both openers fell, Madsen and Leus du Plooy (29 not out) put on 72 for the third wicket, before Alex Hughes smashed the winning boundary in the 18th over.
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