Jersey hearts were broken, and with them a seven-game unbeaten run on home turf, when London Welsh counter-attacked for the winning score with the final play of a tense encounter.
The visitors had the benefit of the slight slope at St Peter plus a stiff north-east wind in the first half, and scored an early try when lock Alex Woolford broke through and crashed over after a series of attacking phases.
Jersey were unable to set up a platform during the first half, partly due to a series of lost lineouts, but the Exiles managed a second score on their next serious visit to their opponents' half, with a series of pick-and-drive attacks ending with a try to Jesse Liston. The home side had to be content with Brendan Cope's late penalty on the stroke of half-time.
An 11-point deficit seemed surmountable for Jersey once the conditions were in their favour, and a second Cope penalty and Nick Haining's try from a rolling maul gave an early boost soon after the resumption, and soon after the hour Cope levelled the scores with his third penalty.
It looked to be Jersey's match for the taking, but a series of attacking opportunities were squandered, with breaks by replacements Sean McCarthy and Jack Moates coming to nothing.
The Exiles had been heavily penalised by referee Mike Hudson for much of the afternoon (an estimated total of 16 concessions to Jersey's nine) and eventually lost prop Ben Cooper to a yellow card for a scrummaging infringement, but Jersey lost their one-man advantage in the closing minutes when Mark Cooke limped off after all his side's replacements had been used.
The draw looked inevitable, but then the seven-man Welsh pack were awarded a penalty at a scrum and former Jersey scrum-half took a quick tapped penalty in a bid to maximise his side's one-man advantage in the back-line. Winger Josh Drauniniu made a powerful 40 metre burst, beating several tackles and getting across the 22-metre line before giving a scoring pass to Chris Elder, who raced to the line and behind the posts. Olly Barkley's conversion was the final kick of the game and completed a 100% record from the tee for the former England fly-half.
"We should have been able to claw back 11 points, but we didn't take the opportunities we created and that's something we'll have to learn from," said Jersey Head Coach Harvey Biljon. "There were times when we got through but were perhaps a bit over-excited which stopped us getting the score.
"It's disappointing as we have trained well this week, but the London Welsh 'voodoo' [four defeats in as many Championship encounters] remains, and hopefully the injuries we've sustained today won't prove too serious."
Ecstatic Welsh Head Coach Rowland Phillips hailed the character of his side in withstanding waves of Jersey pressure in the second half before landing the killer punch.
"Everything seemed to be pointing against us in the closing stages, with Jersey pressure and a yellow card and I'd probably have settled for a draw," he said. "Fair play to the players for having the spirit, the belief and the character to get the winning score - it was an outstanding effort."
JERSEY: Adair; Howe, Evans (Owen 67), Cooke, Lane; Cope, Fisilau (Moates HT); Lockwood (McCarthy 70), Selway (Garcia-Veiga 63), Kerrod (Herriott 70), Phillips (Spinks 70), Campbell, Rae (c), Freeman, Haining (Kolo'ofa'i 53).
LONDON WELSH: Jewell (Carlisle 41); Elder, Reynolds, Armitage, Drauniniu; Barkley, Glynn; Aholelei (Trevett 51), Britton, Cooper (YC 72), McNally (Corker 76), Woolford, Liston (Gilding 76), Hodson, Thorpe (c) (Murphy HT). Not used: Allen, Lewis.
Referee: Michael Hudson (RFU)
Man-of-the-match as chosen by match sponsor Praxis IFM: James Freeman (Jersey)
Half Time: 3-14
Try: Haining 51
Penalties: Cope 40, 51, 62
Tries: Woolford 9, Liston 23, Elder 80
Conversions: Barkley 9, 23, 80
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