Jersey's British and Irish Cup run ended at the semi-final stage despite scoring six tries in a thriller at Yorkshire Carnegie.
The hosts led 26-17 at half-time, thanks to Andy Forsyth, Taylor Prell, Rob O'Donnell and Jonah Holmes scores.
Ross Adair's try after the restart set the tone for a scintillating half with Jersey's Uili Kolo'ofa'i going over twice to set up a tense finale.
Carnegie held on to win by a point and will host London Welsh in the final.
Jersey have now lost their last seven matches against Yorkshire Carnegie and are still waiting for their first win at Headingley.
The islanders took the lead inside three minutes with back rower Nick Haining powering over from close range. But the home side hit back through Forsyth's score after good work from hooker Joe Graham and then rugby league convert Kevin Sinfield set Prell clear for their second try.
Prop O'Donnell found space out wide to crash over and give the Leeds-based team a 19-5 lead before Jersey responded with tries from flanker James Freeman and full-back Adair.
A quickly-taken penalty, however, caught the visitors off guard and Holmes ran in for a converted score which gave Yorkshire Carnegie a nine-point advantage at the break.
It took just 35 seconds of the second half for Jersey to get their fourth try, as Adair crossed in the corner for his second of the afternoon.
It sparked Carnegie into life and after a series of phases captain Ryan Burrows went over to make it 33-22.
The visitors just would not lie down though, and replacement forward Kolo'ofa'i twice scored from mauls to narrow the gap to a single point.
Brendan Cope and centre Lewis Robling shared kicking duties for Jersey, both without much success. Cope missed the conversion of Kolo'ofa'i's second score and with it the chance to take a remarkable lead.
The islanders finished the game with 13 men after Gary Graham and Robling were sent to the sin-bin for infringements near their own line.
But there was still time for more late drama as Jersey felt they should have had a penalty kick to win it, but the referee awarded a scrum and not a penalty when a Carnegie player was lying on top of the ball at a ruck.
After a series of resets Jersey lost possession at the breakdown and Carnegie narrowly hung on. They will have home advantage in the final on Sunday 10, April, with London Welsh the visitors after their 36-15 semi-final win over Cornish Pirates on Saturday.
Yorkshire Carnegie: Holmes; Goss, Forsyth, Casson, Prell; Sinfield, Pilgrim; Beech, Graham, O'Donnell, Schofield, Smith, Jones, Walker, Burrows (capt).
Replacements: Nilsen, Imiolek, Tideswell, Ryder, Saull, Hodgson, Burdon.
Jersey: Adair; Howe, Evans, Robling, Lane; Cope, Dudley; Lockwood, Buckle, Kerrod, Campbell, Phillips, Rae (capt), Freeman, Haining.
Replacements: Lancuba, Selway, Herriott, Kolo'ofa'i, Graham, Sami Fisilau, McCrea.