A virus robbed Rovers of several first-teamers against Crewe in the Johnstone's Paint Trophy on Tuesday night.
McCombe along with fellow defenders Rob Jones and Tommy Spurr and winger Kyle Bennett were among those to be affected.
Everyone trained on Thursday though and are expected to be available for the trip to Wiltshire, except McCombe who is still under the weather.
Paul Keegan is back in the squad after serving a one-match suspension in midweek while fellow midfielder Martin Woods has recovered from a thigh injury.
Billy Paynter's grandmother died this week but the striker is still expected to be included in the travelling party.