Raiders led 20-14 at half-time after two tries from Nielsen and one from Sean O’Hagan, who also kicked a conversion and penalty.
O’Hagan kicked another penalty to make it 23-14 but Barnes hit back to cut the deficit to 23-22 with an unconverted try and penalty.
Kieran Leeming went over for Worthing’s fourth try and Nielsen then touched down his third, which was converted as Raiders moved 35-22 ahead.
Barnes then went over for an unconverted try to make the score 35-27 and that was the way things stayed.
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