Rovers were trailing Hull 16-4 at half-time before they launched a fightback in front of a crowd of 8,500, running out 24-22 winners.
Mike Fletcher scored a last-minute try to send the Rovers' fans into raptures, with other scores coming from Garry Atkins, Mike Fletcher, Paul Fletcher and Paul Rouse.
Tevita Vaikona scored two tries for Hull, who will be playing in the Super League next season.
Andy Corley kept Swinton's unbeaten play-off record intact with a hat- trick of tries to beat Widnes 28-24. Sean Casey also crossed twice for the Lions, with Jamie Bloem collecting a personal points tally of 16 for Widnes, whose hopes of making the quarter-final play-offs are now in tatters.
Paul Cook led the way with seven goals and two tries as Huddersfield brushed aside Hunslet 46-26. Hunslet had kept up the pressure, but two converted tries near the end saw their efforts in vain. On the way to his 22 points he scored the fastest 100 points in Huddersfield's history.
Richard Price scored a hat-trick of tries and landed seven goals as Batley hammered Bramley 54-8.
It was a points feast for Barrow too, who beat Lancashire Lynx 64-24 with their teenage hooker Brett McDermott helping himself to four tries.
Scrum-half Dean Marwood kicked 10 goals plus a drop goal, as Stewart Wilkinson's outfit became only the second team this season to win at Lancashire's Preston headquarters.Reuse content