Surrey, Lancashire and Gloucestershire won their respective T20 Blast quarter-finals to confirm their Finals Day spots at Edgbaston on Saturday.
Surrey’s 56-run win over Kent was set up by a stand of 114 between Jason Roy and Hashim Amla, while Will Jacks took a career-best 4-15 with the ball.
Lancashire skittled Sussex for 95 at Hove to progress to the last four.
And, in Bristol, Gloucestershire bowled out Northants for 113 on their way to a comfortable seven-wicket victory.
Notts Outlaws play Leicestershire Foxes in the remaining quarter-final at Trent Bridge (18:00 BST start).
The two semi-finals and final will all be played on Saturday behind closed doors.
Jacks spins Surrey to Finals Day
England opener Roy struggled for runs during the 50-over international series against Ireland and Australia, registering a highest score of 24 in six innings, but his knock of 72 in Surrey’s final T20 group game against Kent signalled a return to form for the 30-year-old.
Against the same opposition, Roy added 56 in a century partnership with former South Africa batsman Amla (73 not out) to help his side to 169-2 at The Oval.
Off-spinner Jacks then accounted for Kent’s main attacking threats at the top of the order, dismissing England trio Zak Crawley, Joe Denly and Sam Billings, as well as Daniel Bell-Drummond – the leading run-scorer in the group phase.
Surrey will go to Edgbaston as the in-form team, having now won eight consecutive T20 games.
Bowlers were on top at Hove, where Sussex restricted Lancashire to 140-8 in an innings disrupted by a rain delay.
But Sussex were then undone by the visitors’ spinners during their run chase, with Liam Livingstone (4-23), Matt Parkinson (3-9) and Tom Hartley (1-18) sharing eight wickets between them.
Meanwhile, Gloucestershire ended their last-eight hoodoo in the T20 Blast after losing at the quarter-final stage in three of the previous four years.
Victory over Northants rarely looked in doubt after a superb effort bowling first in Bristol.
Benny Howell (3-16), Ryan Higgins (3-24), David Payne (2-14) and Graeme van Buuren (2-17) prevented Northants from posting a challenging total and the home side reached their target with more than eight overs to spare.