Last year's top scorer Ambrose has been out of action with a hamstring injury since New Year's Day, while fellow midfielder Marrow has been struggling with an ankle knock since November.
New manager Dougie Freedman rates the pair at 50/50 to feature this weekend while Jermaine Easter is poised to start his first game for the Eagles.
The striker made his debut as a substitute during last week's 3-0 defeat at Swansea after joining from MK Dons. Defender Lee Hills is still on the sidelines with a knee problem.
Source: PA
