The pair have been out of action since the beginning of the month with thigh and hamstring injuries respectively, but McDowall is hopeful that both players will make the squad.
He told the club's website: "Fran and Ross have both been working at the tail end of last week so they are back running.
"We are hopeful we might get one or two additions to the squad because it is fairly tight. Last week we were operating with 16 because we had six injuries. So we are hopeful those two will join the squad again this weekend."
However, Lee McCulloch is still out with an ankle injury.