Moeen Ali and Alex Hales lead Worcestershire and Nottinghamshire to victories while Kent miss out on topping the South Group.
Lancashire choose not to renew England batsman Haseeb Hameed's contract when it expires at the end of the season.
Essex record an exciting win at South Group leaders Sussex, while Hampshire eased to victory over Middlesex.
Nottinghamshire bowler Luke Fletcher signs a new two-year contract to extend his stay at Trent Bridge into a 13th and 14th season.
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Sussex Sharks captain Luke Wright hopes his side can go one better in this season's T20 Blast.
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