Dirk Nannes snared 5-31 and Craig Kieswetter flayed a breezy 70 as Somerset made it two wins in three days in the NatWest T20 Blast with victory by 34 runs over Sussex Sharks in the South Group at Arundel Castle.
On a slow pitch Somerset's 163 for four always looked like being too much for a Sussex side struggling for confidence in this format, and Nannes finished them off by yorking James Anyon and Chris Liddle with successive deliveries as they were bowled out for 129 in 18.5 overs.
Nannes has played more than 200 games in the format but this was only the second time the 38-year-old had taken five wickets in an innings.
The Australian struck in his second over when Chris Nash, who was restored to the top of Sussex's order, was well held by Alfonso Thomas in the deep.
Luke Wright threatened to provide some momentum when he hit Thomas's first ball for six, but the experienced South African seamer, who had taken four wickets in four balls this week when the sides met in the LV= County Championship, bowled Wright as he attempted to swing through the leg side with his third delivery and from then on Sussex never looked capable of threatening Somerset's score.
Craig Meschede, varying his pace impressively on a sluggish surface, picked up 2-26 and leg-spinner Max Waller snared Sussex's last realistic hope when he had skipper Ed Joyce taken on the midwicket boundary for 25 in the 12th over.
Yasir Arafat struck two fours in an over off Craig Overton to give them brief hope and finished unbeaten on 36 from 23 balls, but Nannes returned to take four wickets in seven deliveries, including three in his final over.
Earlier, Kieswetter had anchored Somerset's innings with 70 off 49 balls.
In the absence of Marcus Trescothick, who is recovering from a groin strain, Kieswetter thrashed 56 in the powerplay with Chris Jones to give the innings a rousing start.
But Sussex clawed it back impressively through Steffan Piolet and, after hitting three fours and a six in the first six overs, Kieswetter was becalmed to such an extent that he only struck one more four until the 17th over, when he took two boundaries off successive balls from left-armer Chris Liddle.
He was eventually caught at long-on in the 18th over, but Alviro Petersen made an unbeaten 29 from 24 balls at the end to propel Somerset to a score which they defended comfortably in the end.
Acting captain James Hildreth said: "It was an excellent performance by us. Craig helped get us to a score which we thought we could defend and then our bowlers did a good job.
"It's good for confidence to win two in a row and we're looking forward to going again on Wednesday against Middlesex at The Oval."
Sussex have now lost five on the spin in the Blast and head coach Mark Robinson had no complaints about the outcome.
"We could have run out Kieswetter three times but it was still a special innings," he said.
"It's a testing time for us at the moment but our players have got to keep putting themselves out there and performing. We've been hit badly by injuries but the bottom line is we need to start playing better."