Swindon duo Kevin Amankwaah (knee) and Vincent Pericard (groin) both resumed training this week but will face last fitness tests.
Midfielder Jonathan Douglas is rated doubtful after picking up a groin injury against Notts County.
Crawley manager Steve Evans told BBC Sussex: "We have to concentrate on our football and our strategy for the match. The boys all want to be in the starting XI.
"Swindon are an attacking side and they're very good going forward. We like to play that way so it's got the hallmarks of being a fantastic game.
"The television cameras aren't here because they think Swindon will roll us over easily. They think maybe, just maybe there might be an upset. We've got to believe we are capable of an upset or there'll be no point in us taking part.
"I would settle now for the 92nd minute and one chance in the entire game falling to Matt Tubbs or Richard Brodie. I would back either of them to stick us in the next round."
Source: BBC Sport