Rangers are boosted by the news that Madjid Bougherra could return.
The defender - who has been out with a hamstring injury - trained on Friday and, if not involved on Saturday, will have a part to play against Dundee United on Tuesday.
Steven Naismith is suspended for the visit of Saints but Richard Foster is back in the squad after sitting out the midweek win at Aberdeen under the terms of his loan agreement.
Michael Higdon and Hugh Murray are suspended for St Mirren.
In-form striker Higdon begins a two-match ban while midfielder Murray is out for one game.
But on-loan Celtic player Paul McGowan returns after being ineligible for the narrow defeat at Parkhead.
Rangers (from): McGregor, Whittaker, Papac, Weir, Wylde, Diouf, Davis, Edu, Ness, Hutton, Lafferty, Jelavic, Healy, Alexander, Kerkar, Fleck, Bougherra, Foster.
St Mirren (from): Gallacher, McAusland, Travner, McGregor, Potter, Thomson, Barron, Goodwin, Dargo, McLean, Van Zanten, Mair, Mooy, McGowan, Cregg, Barron, Samson.