The Reds closed their Championship season with a 13th win - seven of these on the road - to record a second successive fifth-placed finish in English rugby's second tier.
An early try by Auguy Slowik from Scott Van Breda's kick through put the visitors in front, and although skipper Matt Challinor levelled things up from close range, a flurry of points put the Reds 15 clear at the interval. Brendan Cope slotted a penalty, Kieran Hardy raced through a gap and hared to the line, then Van Breda fed Slowik again and this time the winger kicked ahead and won the race to the ball in goal.
The second half was a scrappy affair, with increasing amounts of niggle, but Slowik was able to complete a hat-trick with a good finish in the corner after an assist from - once again - Van Breda.
It looked comfortable for the Reds, even after Cameron Cowell crossed for the home side (12-27) but then things started to go wrong with an astonishing five yellow cards, four of them to visiting players, in the last 22 minutes. First of all Slowik was despatched for a deliberate knock-on, then Rory Bartle and Doncaster's Challinor were sent to the cooler for fighting.
The Knights pulled a try back through Cam Cowell after Jared Saunders had seen yellow for a high/dangerous tackle - the visitors were briefly down to 12 players against their hosts' 14. Knights continued to press and when George Eastwell scrambled in defence to stop a likely try, he too was carded with a penalty try awarded and it was 18-27 with still time to play. The replacement Tom James crossed and the visitors' lead was down to just a single point. The stadium clock read 80 minutes of running time, but in reality there were still around seven minutes to play of official time.
To the Reds' great credit, they dug deep and were able to regain some control in the dying minutes, playing the ball mostly in their opponents half. At one stage it seemed the Knights had stolen the ball and broken clear, but the turnover came from an illegal hand in the ruck, spotted by the assistant referee, and Jersey were given a penalty. With time virtually up, Cope elected to go for goal, slotted the kick and finally the game and the season was over. Wins for Bedford Blues, the Pirates and Yorkshire Carnegie meant it stayed 'as you were' in the league table, with the Reds in fifth.
Jersey Reds
Scott Van Breda (co-capt); Tom Pincus (Jack Macfarlane 66), James Newey (Mark Best 67), George Eastwell (YC 72), Auguy Slowik (YC 57); Brendan Cope, Kieran Hardy; Jake Woolmore (co-capt) (Roy Godfrey 66), Jared Saunders (YC 65, Josh Hodson 75), Jake Armstrong (Leeroy Atalifo 66), Jerry Sexton, Uili Kolo'ofa'i (Tom Quarrie 51), Rory Bartle (YC 60), Jake Upfield, Matt Rogerson.
Unused replacement: Alex Dolly
Doncaster Knights
Cameron Cowell; Andy Bulumakau (Charlie Foley 56), Lesley Klim, Lloyd Hayes, Curtis Wilson; Simon Humberstone, Michael Heaney (Tom James 51); Richard List (Jack Bergmanas 51), Ben Hunter (Curtis Langdon 61), Joe Sproston (Colin Quigley 51), Matt Challinor (capt) (YC 60), Tom Hicks (Nick Civetta h-t), Jason Hill (Adam Batt h-t), Alex Shaw, Josh Tyrell.
REFEREE: Hamish Smales Assistants: Matt Daubney, Rob Warburton
ATTENDANCE: 1,675
Half Time: 7-22
Scorers
Doncaster Knights
Tries: Challinor 20, Cowell 69, Penalty Try 72, James 73
Conversions: Humberstone 20, 73
Jersey Reds
Tries: Slowik 9, 29, 50, Hardy 26
Conversions: Cope 9, 29
Penalties: Cope 23, 80