Previously unbeaten on their travels the Dons slumped to a second successive away defeat as Workington Town posted a 34-6 victory.
Despite lacking several regulars, the Dons can have few complaints about the result with Town, who drew level on points with them as a result, scoring six tries against one.
Keen to bounce back from a 44-8 defeat at second-placed York City Knights, the Cumbrians made the early running and it needed good defence to deny wing Elliott Miller a try in the corner.
There was no stopping the Town man a couple of minutes later, however, when he got on the end of a clever cross-field kick by play-maker Jamie Doran to touch down for an unconverted try.
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The Dons suffered another early blow when losing loose-forward Brandan Wilkinson after nine minutes.
Despite having a numerical advantage for ten minutes while Town prop Tom Curwen cooled his heels in the sin bin following a high tackle on scrum-half Jordie Hedges, the Dons failed to put the home side under any real pressure.
They fell further behind on 24 minutes when Town full-back Sam Forrester joined the line and sent Miller over for a second try which scrum-half Carl Forber converted to make it 10-0.
The South Yorkshire side would probably have settled for that score-line at the break but Town struck twice in the closing minutes of a largely one-sided first half to come in leading 22-0.
Giant Tongan international Fuifui Moi Moi, as he has regularly done against better sides than the Dons over the years, powered his way over at the side of the posts on 35 minutes.
Centre Perry Singleton claimed his seventh try of the season on the hooter which Forber again converted.
The Dons knew that they had to score the next try after the break to entertain any comeback hopes.
They did just that on 54 minutes when Jack Sanderson, standing in for the injured Richard Owen at full-back, supplied the try-scoring pass to centre Cameron Scott.
Hedged added the touchline conversion to make it 22-6.
The Dons still had a mountain to climb, almost as high at the Lakeland fells in the distance, but at least they had a foothold in the game.
But they failed to build any momentum and Town put the result beyond doubt on 67 minutes when Doran weaved his way through some weak defence to touch down near enough for Forber to added the extras.
The visitors made a spirited response and second-rower Brad England looked to have grabbed a second try on 74 minutes only for the referee to spot an obstruction in the build-up.
Fittingly, Town had the final word with former Super League star Moi Moi bagging his second try, again converted by Forber, three minutes from time.
Dons: Sanderson, Jones-Bishop, Scott, Tali, Doherty, Howden, Hedges; Boyle, Kesik, Bienek, England, Lane, Wilkinson. Subs: Scott, Spiers, Muranka, Cross.