In the end Hampshire came up just short with Warwickshire progressing to face Durham in the final.
Despite having the better of the opening half hour, three tries for the home side in the space of 11 minutes, either side of the half-time interval, were to be Hampshire undoing.
It proved an end-to-end contest on a glorious day.
A draw would have been sufficient to see Hampshire through.
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And Perkins scored again with Joel Knight adding the extras. Then Curtis Barnes crossed under the posts with just five minutes remaining but the try from the Portsmouth man was disallowed.
Boss Ian Chandler was disappointed it wasn’t given but praised the two teams for a great match.
He said: ‘It has been another great campaign and it is just a shame it ended the way it did.
‘The referee awarded us the try two minutes from the end but disallowed it when the touch-judge flagged for a minor offence.
‘Even the opposition coach said it was a harsh call.
‘It was fantastic game, though, and shows there is a future for county rugby.’
Hampshire were impressive on the attack but found the Warwickshire defence resolute in the early periods.
However, they were powerless to stop Jacob Knight going over after an excellent steal from the Warwickshire lineout from Liam Perkins.
Warwickshire responded and winger James Neal was on the end of a swift move to level the scores.
The visitors took full advantage of the 10 minute absence of influential fly-half Dan O’Brien to post a Joel Knight penalty.
And when prop George Primett burrowed over from close range, again converted by the senior Knight, Hampshire were in control at 17-7 with nine minutes to play before the break.
Warwickshire stormed back before the end of the first half to level. Then the home side added two more tries in the opening five minutes of the second period before the late drama.