The Reds rallied after a below-par first half and scored 24 points in the final quarter to seal an eventually emphatic victory. The result condemned Rotherham Titans to relegation after 14 seasons in the Championship and 22 at the top two levels.
The Yorkshiremen had been good value for their half-time lead, but when the Reds asserted themselves late in the game, the writing was on the wall for the visitors.
Jersey wing Jason Worrall struck early after a second-half hat-trick in his previous match, racing over in the corner after just four minutes following quick hands from his team-mates inside. But the Reds conceded a stream of penalties and this gave the Titans the platform for an equalising try, finished by Rhodri Davies as the scrum-half wriggled over from the back of a maul.
Two Caolan Ryan penalties helped the visitors to a six-point lead at the break, and they could have had other tries but for a crucial turnover won by Mark Best and a tackle in the corner by Scott Van Breda as Davies looked to add his second.
Rotherham finished the half with 14 men after Jamie Cooke saw yellow for a late and high challenge on Worrall, and the Reds took advantage almost straight from the restart when Apakuki Ma'afu ghosted through after Joel Dudley picked up a loose ball.
Ryan restored his side's lead, but on the hour the Reds rumbled over from a maul, and then Jake Armstrong fed Dudley for the bonus-point score after a surging run which saw him choose the scrum-half inside him rather than Van Breda outside. The lead was stretched thanks to a long-range penalty from Van Breda, who then turned provider with a scoring pass to Kieran Hardy having taken a superb back-handed off-load from Best.
Jersey Head Coach Harvey Biljon was pleased with his players' reaction to falling behind.
"We weren't surprised to be playing an emotionally-charged team, and in the first half they were more accurate than us," he said. "But we did well to get back on track and hold on to the ball, and our finishing towards the end was sharp and helped us nail down a good win.
"We have a quick turn-around now before our Cup quarter-final, the boys will have Sunday to recover and then we'll be in on Monday for a really intense week. We're looking to deliver a knock-out display for our supporters on Friday and we hope they'll turn out in good numbers."
"It's a sad day for the club as one of the longest-serving teams in the league," said Titans' Head Coach Nic Rouse. "We knew we would need to put in a performance and to be fair we'd done that in the first half, although I thought we left some scores out there.
"Ultimately we weren't ruthless enough but I can't fault the effort of the players, they had nothing left to give."
JERSEY REDS: Van Breda (c) ; Newey, Ma'afu (Best 23-33, 67), Eastwell , Worrall ; Cope , Dudley (Hardy 66); Godfrey (c) (Woolmore 61), Saunders (Selway 56), Atalifo (Armstrong 56), Sexton , Mckern (Kolo'ofa'i 51), Bartle (Upfield 73), Joyce, Argyle .
ROTHERHAM TITANS: Thomas; Foley, Cooke (YC 37, Odogwu 47), Barker, Henry (Millar 66); Ryan, Davies (Porter 59); Toby Williams (Tom Williams 72), Cole (Dolly 70), Foster (Palmer 70), Louw, Peters, Grange, Maddison (Burns 73), Calladine (c).
REFEREE: Mike Hudson. Assistants: Darryl Chapman, Michael Patz
ATTENDANCE: 1,589
Half Time: 7-13
Scorers
Jersey Reds
Tries: Worrall 4, Ma'afu 42, Selway 60, Dudley 64, Hardy 77
Conversions: Cope 4, 42, 60, 64, 77
Penalty: Van Breda 69
Rotherham Titans
Try: Davies 9
Conversion: Ryan 9
Penalties: Ryan 14, 23, 47
