Doncaster Knights 46 Nottingham 42: Knights in storming fightback to delight Howells
Three tries came in the last seven minutes, two of them in stoppage time.
Nottingham will see it as a game they should have won but they had been gifted two tries and numerous penalty opportunities that were gratefully accepted by fly-half James Arlidge.
Knights director of rugby Lynn Howells was delighted after having made four changes from the side that had narrowly lost at Worcester.
Dougie Flockhart returned on the wing in place of Oli Goss, fit- again forwards talisman Glen Kenworthy came in for youngster Dom Parsons and, in the back-row, Andy Boyde replaced injury victim Ed Jackson and Irishman Zack Farivarz made his first Championship start in place of Leeds' dual registered youngster Chris Walker.
Knights fly-half Tristan Roberts kicked a fourth-minute penalty and when they counter-attacked from deep inside their own halffull-back Steve McColl was on hand to take the final scoring pass to dive over in the corner.
Roberts added a penalty but Nottingham centre Jack Cobden intercepted and chipped ahead for No 8 Sione Kalimafoni to kick on and outpace the cover before picking up and diving over for a try that was converted by Arlidge.
Roberts kicked three more penalties before the break but Arlidge kicked four on the rare occasions that Nottingham got into the opposition half.
Turning around only 20-19 ahead in spite of having enjoyed most of the territorial advantage, the Knights could have increased their lead from the outset but Flockhart was hauled down after a 50-metre.
Then, in the space of 10 minutes, the Knights did their best to throw the game away as their inexperience led them to concede two tries, both converted by Arlidge, who also kicked a penalty.
The first try came through winger Andrew Savage after a poor clearance kick and the second by flanker Tom Armes came when the Knights were caught asleep at the back of a long lineout just inside their own 22.
The Knights pack then gained possession and hooker Steve Boden was driven over for a try that was converted by Roberts.
Replacement prop Stuart Corsar was yellow-carded for a technical offence and Arlidge kicked the resultant penalty.
Hardly had Corsar returned than the Knights were penalised again and Arlidge continued his 100 per cent record for the day with his seventh penalty.
The Knights threw caution to the wind and with lock Matt Challinor and replacement flanker Walker to the fore, took the game to Nottingham.
Capt ain Neil Cochrane broke through from a quick tap penalty just outside his own 22 and made 40 metres before linking with Corsar, who fed Challinor to pop the ball up to supporting centre Chris Briers, who ran the final 30 metres to score a try that Roberts converted.
Knights' cause was helped when Nottingham captain Craig Hammond was sin-binned for killing the ball close to his own posts.
With three minutes of stoppage time left, the Knights opted for a scrum instead of kicking the penalty that would have brought them within bonus point distance and they were rewarded with a penalty try following Nottingham's scrummaging infringements. Roberts's conversion brought the Knights to within a point and there was one minute left.
Knights gathered the restart but lost possession 35 metres out, giving Nottingham a scrum with just 10 seconds left. The Doncaster pack destroyed the depleted Nottingham pack to regain possession and the ball was moved through several phases of play.
From the last of these, two long passes to the right by Roberts and centre Gidlow allowed Flockhart to run a perfect line to cut inside his opposite number and race 55 metres to score his side's winning try with the last play of the game.
Doncaster Knights: McColl (Goss 73), Flockhart, Briers, Gidlow, Williams, Roberts, Hallam (Jerecevich 80), Frazier (Corsar 49), Boden, Cusack (Thiede 51), Kenworthy (Parsons 78), Challinor, Cochrane, Boyde (Cusack 59 & 66), Farivarz (Walker 51). Unused: Doughty.
Nottingham: Sempere, Savage, Streather (Marshall 25), Cobden (Shaw 73), Jackson, Arlidge, Barnham (Roussaire 68), French, Farrell, Adams (Buxton 54), Green, Hemmingway, Hammond, Kalimafoni, Armes (Sherriff), Unused: Majewski, Davies.