Doncaster coach Tony Miller must find a way to deal with the departure of captain Craig Lawton, who left the club this week after a change in his work commitments.
The Dons lost 34-20 at Derwent Park, but coach Tony Miller remained upbeat afterwards.
He said: “We won the second half 20-18, which was pleasing because that’s something that we’ve been working hard on in training.
“I also thought we played the better rugby and scored the better tries.”
The Lions were beaten 58-6 by Batley, with Phil Joseph registering Swinton’s only try in a one-sided affair.
Smith now has just four days to boost morale and secure a victory that could push the Lions back into the Co-operative Championship One play-off places.