Kent 307 for 8 (Kuhn 127, Rouse 70, Blake 61, Brown 3-53) beat Worcestershire 306 for 6 (Cox 122*, D'Oliveira 78, Barnard 50) by two wickets
So now we know that Heino Kuhn is not unstoppable; it is just that Worcestershire did not stop him soon enough. Kent will contest the Royal London Cup final thanks to Kuhn's fourth hundred in five matches, all of them in the 50-over competition, but the ball before they secured their two-wicket victory in a stomach-churning final over at New Road, Kuhn was holding back the tears as he left the field grim-faced fearing another magnificent display had this time ended in failure.
Kuhn was 121 not out as Worcestershire sought to defend 11 off the final over, the task at the end of a wonderful semi-final handed to their 19-year-old seamer, Pat Brown, whose experience stretched to 16 matches across all competitions. Brown, attempting a full delivery for the first time, watched his second ball sail over his head for six, only to produce a nerveless response by deceiving Kuhn with a knuckle ball with his next and have him caught at short midwicket.
The youngster, only playing because of injuries to Joe Leach and Josh Tongue, had outwitted county cricket's form batsman, only for Harry Podmore, who had achieved something of a miracle by crossing while the ball was in the air, to strike Brown's next ball over mid-off to take the game.
Kent now await the winners of Monday' s semi-final between Hampshire and Yorkshire, leaving Worcestershire to come to terms with defeat in a semi-final for the second successive year.
This was not Kuhn's most attractive century in the sequence by any means, but his game craft after Kent lost 3 for 31 in pursuit of 307 was once again excellent. Worcestershire will forever rue the simple return catch Daryl Mitchell shelled when the South African was 50. That enabled Kuhn and Alex Blake, who contributed an open-your-shoulders 61, to add a decisive 115 in 14 overs for the sixth wicket.
By the time Blake fell at long-off, Kent were in sight of the line. Ed Barnard produced two excellent overs at the death, underlining what his innovative half century had shown earlier - that here is an allrounder who relishes the pressure - but to no avail.
All that meant that Ben Cox might feel that this was another game when his excellence was overshadowed through no fault of his own. Such is the competition among England's young wicketkeepers that, even at 26, Cox cannot be sure that he will one day win the England opportunity that many down Worcester way are adamant he deserves, but his reputation has risen another notch even if his maiden hundred in 50-over cricket failed to take Worcestershire to their first Lord's final for 14 years.
Beneath the Big Three of Jonny Bairstow, Jos Buttler and Sam Billings, county cricket can take pride in some natural glovemen who would have passed muster in any era, Ben Foakes and Ryan Davies among them, and Cox's undoubted talents will be more widely recognised after he backed up his usual exemplary display behind the stumps with an unbeaten 122 from 106 balls which revived Worcestershire.
They had subsided to 48 for 4 by the time the cathedral clock showed noon, but Cox, find willing allies in Brett D'Oliveira and Barnard, swept them to 306 for 6 with a potent combination of energetic scampers, powerful blows and judicious improvisation.
Worcestershire's early wobble was one wicket away from feeling terminal. Matt Henry, Kent's incisive and influential Kiwi, struck immediately by having George Rhodes caught at slip. Podmore silenced Callum Ferguson, who looked in mint form before he shuffled across his stumps to be lbw, Darren Stevens, cricket's version of the Baobab tree, bowled through a canny spell in which Joe Clarke failed to hit him over the top and Mitchell was bowled off his pads ad he tried to make room.
Cox, though, has had an excellent tournament. He secured Worcestershire's semi-final spot with 80 from 85 balls in their final group game victory against Warwickshire. Stevens might have bowled both him and D'Oliveira before marking the end of his spell by munching a banana. The stand swelled to 140 from 24 overs before D'Oliveira, who should have been stumped on 45 against Denly's legspin, fell to a full toss from the same bowler when 78, a brilliant one-handed catch in the deep by Henry.
If Calum Haggett had not wandered infield from long leg, Cox would have fallen to the hook shot on 82, which equalled his previous best; the bowler, Podmore was furious. There was another nervy moment on 95 when the small scoreboard showed him on 109 and the crowd's jeers caused him to momentarily lose concentration: when you are chasing a maiden hundred, the last thing you need is for the scoreboard to award you a fantasy one.
But Worcestershire regathered and 44 came from the last two overs as Cox was backed up by Barnard's 50 from 28 balls, an innings of wonderful invention.
Cox judged that Worcestershire's 306 was "about par". The average score at Worcester in this season's Royal London Cup was 349, but this was a used pitch and there was a little bit of encouragement for the new ball. But Kent recovered from early damage as Worcestershire had earlier as Kuhn added to hundreds already logged against Surrey, Gloucestershire and Nottinghamshire.
Lord's was theirs and Billings, who seems fated never to get near the side he has been chosen to captain, will pray that he can surf Kuhn's wave and make a contribution when it most matters.