Last season’s National One champions defended solidly throughout and took their chances well.
The Cumbrians were the first to threaten, full-back Brett Carter being held on his back over the line on 10 minutes after darting past several defenders.
Dennis Tufour came to Doncaster’s rescue on 15 minutes when intercepting Mark Calderwood’s inside try-scoring pass to scrum-half Carl Forber following a spell of home pressure.
Town continued to look the better side and they should have taken the lead after creating an overlap before Tuffour touched down for a 20th-minute try – goaled by Bobby Goulding – from Craig Fawcett’s kick.
Boosted by the score, Doncaster began to get into their stride and they increased their lead on 28 minutes with an unconverted try by centre Danny Cowling following good work down the right flank by Tuffour. Town made a determined start to the second half with a break by Carter deserving better reward and second-rower Jarrad Stack being held on his back over the line.
Doncaster rode their luck and increased their lead on 52 minutes with a close-range try by winger Liam Kay.
Grant Edwards put the result beyond doubt on 63 minutes when breaking the line in the Town 20. Goulding’s conversion made it 20-0.
Big prop Brett Waller ploughed over for Doncaster’s fifth try on 71 minutes.
Winger John Patrick touched down in the corner for a late consolation try for Town.
Doncaster: Waterman, Tuffour, Cowling, Clare, Kay, Cooke, Fawcett, Carbutt, Kesik, Waller, Kelly, Spurr, Goulding. Substitutes: Robinson, Emmett, Edwards, Trout.
Workington Town: Carter, Patrick,Hulme, Morris, Calderwood, Lupton, Forber, Dowes, Phillips, Walne, Phillips, Stack, Olstrum. Substitutes: Coyle, Thackray, Acton, Gore
Referee: T Alibert (France).