Somerset 162 for 4 (Abel 47*, Thomas 42) lost Sussex 158 for 9 (Ward 39, Green 4-17)
The result ensured Somerset secured a quarter-final spot and secured their home tie with one group game left to play.
The batting highlights of the Sharks’ six-over powerplay included three consecutive fours from Daniel Hughes in the third over off Craig Overton and Ward’s first six of the game off Jake Ward in the fifth over.
Hughes fell earlier in the over, missing a bull shot at mid-on, leaving Sussex 49 for 1 at the end of the powerplay. It was 66 for 1 when Ward welcomed Jack Leach’s debut with his first four and a six. Two births.
But the England left-arm spinner quickly bounced back by catching the opener sweeping after facing 23 balls, and that was as much of a screw-up in the middle overs as it got for the visitors.
Green struck twice in his first over, dismissing Tom Clarke and John Simpson for catches in the deep, including a diving effort from Thomas, and the Sharks were struggling at 71 for 4 at the halfway mark of their innings.
Tom Alsop was dropped by Thomas in the first ball of the 13th over, sent by Green, but was dismissed on the next ball as Overton took a comfortable catch at mid-on on a full toss.
James Coles, who scored a blistering 26, and Nathan McAndrew (20) were penalized for checking Dixon’s arm on the boundary, both run out trying to make it two, and Green took his fourth wicket when caught by the same fielder. A simple catch from McAndrew.
The Sussex total may not be enough. Tom Panton and Thomas got Somerset off to a flying start with 34 from four overs, which ended when Panton took a catch at deep square off Mills on the first ball of the match.
Abel escaped Mills with a catch and delivery, but the fast bowler then dropped a catch at deep cover to Koehler-Cotmore for 20 in the tenth over. As Abel and Dixon both cleared the ropes, Dixon ended any doubt about the result with three consecutive fours off McAndrew at the start of the 13th over.
With ten runs needed, Dixon was run out by Clarke’s direct hit from the boundary, but he had already done his job.