Durham have booked their place at T20 Finals Day, after beating Gloucestershire by 19 runs at the Brigthside Ground in Bristol.
Batting first, Durham posted 180-5 from their 20 overs, with Surrey-bound opener Mark Stoneman top scoring with 61.
In response, Gloucestershire had a horror start, falling to 43-4 and despite 80 from Jack Taylor, they went down to a surprise defeat. Having finished top of the South Group, home advantage mae little difference as Durham triumphed in the first ever meeting between these two sides in T20 history.
Stoneman 61 helps Durham post 180
Having won the toss and chosen to bat, Durham struggled in the opening moments, scoring just six off the first two overs, before openers Mark Stoneman and Keaton Jennings started to get into their stride.
Targetting the short straight boundaries, the pair had reached 51 at the end of the six-over powerplay, before then taking the score to 81 without loss at the midpoint of the innings.
Stoneman looked good at the crease and had reached 61 from 40 deliveries, before he was the first man to lose his wicket, slapping a delivery from Benny Howell straight down the throat of Hamish Marshall at long-on to leave Durham 96-1 in the 11th.
Soon after, Jennings joined Stoneman back in the dug-out after he was bowled by Andrew Tye for 36 off 30 balls, with youngster Jack Burnham then next to fall in the 14th over when he found Marshall on the fence off the bowling of Tom Smith.
Durham soon re-grouped, and the partnership of Gordon Muchall and Michael Richardson saw them add 56 in the space of 25 deliveries. Richardson was the aggressor, smashing three sixes in his innings of 37 to help the visitors add 99 in the second half of the innings.
Matt Taylor took two wickets in the final over with consecutive deliveries, which included a third catch for Marshall, but it couldn't stop Durham setting an imposing total of 180 from their 20.
Early wickets see Gloucestershire fall to defeat
In their response, Gloucestershire made an equally slow start to their opponents scoring just six off the first two overs. Unfortunately for the home side, they had lost two wickets.
Mark Wood was the main man early up for Durham, and his excess pace accounted for the wickets of both Hamish Marshall (4) and Ian Cockbain (0) in the space of three deliveries, each of them caught by Jennings on the leg side.
The main wicket Durham wanted early on though was that of Michael Klinger's, and that came their way at the end of the fifth over. Having taken Chris Rushworth for three consecutive boundaries, Klinger nicked behind a shorter delivery which saw Richardson take an excellent catch behind the stumps standing up to put Durham in control.
Wickets continued to tumble after that and when Gloucestershire fell to 91-7 with the wicket of Smith all hope seemed lost.
Jack Taylor had other ideas though, and he gave Durham an almighty scare with 80 from 40 balls, but it wasn't to be as Gloucestershire fell to a 19 run defeat.