A two-game winning run came to an end for Clive Griffiths’ men as ex-Premiership side Worcester took the spoils.
The Castle Park fortress was dealt a blow on Saturday afternoon as their 16-month unbeaten run was dented by a powerful Warriors pack.
Four tries from Worcester, including Ryan Bower, Sam Smith and Max Stelling, as well as Ignacio Mieres penalties and conversions proved enough as Doncaster could only respond through three Dougie Flockhart penalties and a penalty try as the Warriors took the vital bonus-point victory.
Knights: 15 Jarvis, 14 Flockhart, 13 Clark, 12 Armitage, 11 Lewis, 10 Lennard, 9 Palu, 1 List, 2 Hunter, 3 Quigley, 4 Challinor, 5 Hotson, 6 Makaafi, 7 Hills (c), 8 Shaw. Subs: 16 T.Davies, 17 Bergmanas, 18 R.Davies, 19 Phelan, 20 Eggleshaw, 21 Bulumakau, 22 Bravo.
Worcester: 15 Howard, 14 Smith, 13 Grove, 12 Symons, 11 Biggs, 10 Mieres, 9 Mulchrone, 1 Bower, 2 Annett, 3 Schonert, 4 Percival, 5 Sanderson, 6 Williams (c), 7 Betty, 8 Van Velze. Subs: 16 George, 17 Daniels, 18 Rapava Ruskin, 19 Cox, 20 Arr, 21 Eden, 22 Stelling.