|Bob Willis Trophy, Blackfinch New Road (day four):|
|Somerset 251 & 193: Lammonby 107*; Barnard 4-25|
|Worcestershire 200 & 184: Cox 32; Davey 3-16, Gregory 3-65|
|Somerset (21 pts) beat Worcestershire (4 pts) by 60 runs|
Somerset made certain of a place in the Bob Willis Trophy final later this month by wrapping up a 60-run victory over Worcestershire at New Road.
Chasing a target of 245, the home side began the final day on 58-2 but were bowled out for 184 mid-way through the afternoon session.
Ben Cox's 32 was the top score for Worcestershire as Josh Davey and Lewis Gregory took three wickets each.
Somerset will face Essex at Lord's, starting on 23 September.
Their total of 97 points was the highest of the three group winners, seven more than Essex and 10 more than Yorkshire.
And once again, it was the potency of Somerset's seam attack - Jamie Overton's recent departure to Surrey notwithstanding - that made the difference as they completed their fourth win in five group games.
Accuracy brought rewards, with five of the eight batsmen dismissed departing leg-before against a Worcestershire side that could have made the final had they won the match.
Tom Fell (20) played slightly across the line to Gregory and Jack Haynes (30) was guilty of a fatal misjudgement as he shouldered arms to one that nipped back from Davey.
Riki Wessels pulled Davey to mid-wicket and Brett D'Oliveira fell to the final ball before lunch as Craig Overton had him lbw for 28.
Overton struck again soon after the re-start as Ed Barnard edged to third slip, but Cox and Joe Leach halted the slide with a partnership of 44.
Cox was dropped at third man off Davey, but the return of Jack Brooks saw the swift dismissals of Leach (17) and Dillon Pennington - again trapped in front by straight deliveries.
The end came in the 72nd over of the innings as Davey found the edge of Cox's bat and wicketkeeper Steven Davies took a comfortable catch.
Somerset, runners-up in the Championship five times since 2010, will now go to Lord's in search of the first red-ball trophy in the club's history.
Worcestershire head coach Alex Gidman told BBC Hereford & Worcester:
"If we look at the whole competition, once the emotion has gone, we can look back and say we've made significant strides.
"But we've met competition in this game that are better than us and we need to use that as motivation. Somerset are an outstanding team. The better team won this fixture.
"Tom Lammonby's hundred was right up there with any first-class hundred I've seen. For a young man to stand up and play such an important innings, absolute credit to him. It was an outstanding innings and probably the difference in the game."
Somerset captain Tom Abell:
"On the whole I felt we kept our composure really well. Of course, you always want more runs on the board but we always felt it was going to be a tricky chase because it was tough to score.
"With the way we are bowling at the moment, we are asking lots of questions of every batting side. We stuck in, kept asking questions and bowled fantastically well and kept taking wickets at key times. That's what we have done all season.
"Of course, we wouldn't have been in the position without the efforts of Lammers. That was an innings far beyond his years. To play with that temperament and skill, especially when there were wickets falling all around him, I can't speak highly enough of that innings. It is one of the best I've seen, for sure."