Sussex will meet Worcestershire in the Vitality Blast Final after comfortably beating Somerset by in the semi-final.
Sussex set Somerset 203 to win but Luke Wright's men bowled well to restrict them to
Luke Wright and David Wiese set up a daunting target for Somerset to chase in what was a brutal assault at times.
Phil Salt and Wright opened and it was the former who got off to a flyer with three fours but he fell in the second over, caught by Max Waller off of Jerome Taylor's bowling.
Wright counter attacked and hit two huge sixes off Jamie Overton. Laurie Evans, the Sharks' top scorer in the competition, soon followed, trapped lbw by a Taylor full toss leaving Sussex 44-2.
The impressive Delray Rawlins then joined his skipper and again played some eye-catching shots but was caught by Steven Davies off the bowling of Max Waller for 18.
David Wiese joined Wright and the pair worked the singles well and took the Sharks to 91-3 at the halfway stage. The pair then pressed their foot on the gas and Wiese enjoyed a four and six from successive balls from Roelof van der Merwe before Wright launched a brutal assault on Jamie Overton, whose figures after three overs were 0-50 - with 31 coming off the 13th over.
It didn't stop there. Wright hit two successive sixes in the 15th before Wiese went four, six (the biggest of the day), four to take the score to 177-3 from 15 overs - and 58 runs coming from just two overs.
The pair continued their assault and Wiese brought up his 50 just before Wright fell for a brilliant 92 from 53 balls, including seven sixes.
Burgess soon followed, caught by Waller off Taylor, before Wiese went next ball, caught by Johann Myburgh for 52 from 29 balls. Taylor finished with 4-20.
Chris Jordan and Jofra Archer both fell in the final over as Sussex finished on 202-8.
In reply, Sussex got off to a great start with Archer removing Steve Davies and Johann Myburgh, caught by Danny Briggs and Rawlins respectively, inside the first three overs. Somerset at that stage were 24-2. It was soon 33-3 as Wiese pulled off a good diving catch off the bowling of Jordan and Sussex were in full control.
Tom Abell and Corey Anderson added some stability and Abell in particular looked in good touch. One over saw him take a particular liking to Briggs. But the spinner thought he had his men when Evans and Salt combined to take a wonderful catch on the boundary - only to be denied as Evans foot brushed the boundary rope.
At the halfway stage Somerset were 85-4 - only six runs behind where Sussex were at the same stage.
Anderson was dropped by Wiese in the deep soon after before Abell reverse slapped Beer twice for four. Anderson then hit Wiese for consecutive sixes and you could feel the pressure building on Sussex - and it was no more evident when Archer somehow let a ball go to the boundary after an Anderson cut.
The New Zealander then hit Mills for a big six over cow corner. But a bit of luck for Sussex got them the breakthough. Anderson smashed a straight drive, Briggs got a touch onto the stumps and Abell was caught out of his crease.
The momentum was well and truly with Sussex again and the 17th over saw just two runs scored leaving Somerset needing 60 from the final three overs.
The scoreboard pressure got too much for Somerset and Anderson and Gregory went in quick succession. They were left needing 43 from Mills' final over but by then Sussex had done enough. Mills bowled Overton in the final over and Sussex won by 35 runs.
The final between them and the Rapids will be the first T20 meeting between the sides.
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