Montano is troubled with a thigh strain while fellow winger Croft is hampered by an ankle knock.
However, manager Paul Dickov is banking on both players being available as Latics look to continue their promising start to December which has yielded back-to-back wins.
Dickov will be without goalkeeper Dean Bouzanis once more, though, as he completes a three-match suspension following his sending off against Doncaster.
In Bouzanis' absence, Alex Cisak will remain between the sticks after keeping a clean-sheet in Oldham's last outing against Colchester.
Dickov's men have won four of their last five outings and will fancy their chances of defeating a Swindon side without a victory in their previous three contests.
The game is subject to a pitch inspection at 9.30 on Saturday morning owing to the recent cold weather.