A Old Rishworthians side already missing several players lost three forwards to injury before half-time and went down 34-16 at Barnsley.
They handed three tries to a strong-looking home side and although the Copley men scored two excellent late tries as Barnsley tired, it was too late.
Rishworthians opened the Yorkshire Two game brightly and were on top for the first 10 minutes against a much heavier home pack.
Left wing Rhys Town had a strong early run and the aggressive Rishworthian defence won them a penalty for Aaron Canning to give them the lead.
The home side soon drew level with a penalty of their own before Canning went close after good work by the backs.
However, player coach Chris Stone and No 8 Nick Faulkner went off injured in quick succession and the home forwards drove through for a converted pushover try.
Canning added a second penalty but then outstanding flanker Harvey Keighley-Payne also went off injured.
It meant Rishworthians had to use all three replacements and scrum half Gary Morris had to move into the pack.
The home side got another pushover try, this time unconverted, to end the first half 15-6 up.
Rishworthians were still well in it but started to make mistakes.
A misdirected pass handed an unconverted try to the home side soon after the restart and their game went to pieces, allowing another easy try to make it 27-6.
Rishworthians rallied and almost scored from a lineout, but a dropped ball in attack was picked up and Barnsley scored an easy converted try.
The visitors might have collapsed but instead showed why they are an 80-minute team.
They camped in the home 22 and eventually the pressure told. Prop Ryan Mudd set up the ball well from a tap penalty and it went along the line for Town to score in the corner.
Rishworthians were passing and running well and it was no surprise when centre Jack Ledgard finished off another excellent backs move in the other corner.