Durham prevailed over Somerset following a super over, while there were heavy wins for Surrey, The Blaze and Kent
Sterre Kalis hit a stunning season's best 83 not out as Yorkshire shocked tier one opposition in the Essex Eagles at Headingley to win by 11 runs and make it through to the quarter-finals of the T20 Women's County Cup.
The Netherlands international was in imperious touch in hitting 14 fours and one leg-side six as the White Rose totalled 188 for 4 from their 20 overs, including a senior best score of 43 for unbeaten Maddie Ward.
Those two shared an unbroken fifth-wicket partnership of 113 in the last 10.4 overs of the home innings.
Essex's bowlers failed to build any pressure as Kalis and Ward were powerful and inventive, and the Eagles rarely looked like reeling in the 189 target as Yorkshire made it six wins from six matches across all competitions.
The Eagles finished on 177 for 8, with Beth Langston successfully defending 20 runs off the last over.
Victory tees up a last-eight meeting with Bears - who eased past Devon on Sunday (May 18) - with the winner progressing to Finals Day at Taunton on May 26.
Surrey took their place in the quarter-finals courtesy of a 57-run triumph over Hampshire at Beckenham.
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Opener Kira Chathli struck 95 as part of a 110-run second-wicket stand with Alice Capsey, who backed up her century in the One Day Cup with an unbeaten 89.
Set 238, Maia Bouchier and Ella McCaughan put on 74 in five overs, but when Ryana Macdonald-Gay struck, as the former failed to clear Alice Davidson-Richards, it sparked a collapse.
Hawks were eventually dismissed for 180 to end their run.
Durham will be Surrey's opponents after they prevailed in a super over against Somerset.
After both sides registered 124 for 9 from their 20 overs, Mady Villiers conceded just eight, removing Heather Knight and Rebecca Odgers, before Bess Heath knocked off the target of nine thanks to successive boundaries off Charlie Dean.
Tier two Leicestershire will host Lancashire after both sides secured handsome wins over Northamptonshire and Glamorgan, respectively.
The other quarter-final pits Kent, who saw off Cambridgeshire at Fenner's by 80 runs, take on The Blaze who thumped Oxfordshire by 10 wickets.
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