Crawley skipper Josh Simpson will miss the visit of the Bees.
The midfielder was sidelined for Saturday's 1-0 win at Leyton Orient with an ankle injury and is still awaiting the results of a scan.
Kyle McFadzean will also be absent although the defender, who has been out since November following a virus, is back in training and has been pencilled in for a reserve game later this week.
On-loan Millwall striker Aiden O'Brien made his debut as a late sub against Orient and should be involved again, while defender Connor Essam is still awaiting his first taste of action following his January switch from Gillingham.
But boss Richie Barker is unlikely to tinker too much after Town picked up their first win in six matches against the O's.
Brentford boss Uwe Rosler is set to make changes for the trip to the Red Devils.
The Bees missed the chance to close the gap on the play-off places after a lacklustre goalless draw with Walsall on Saturday.
On-loan Wigan defender Rob Kiernan is still out with a knee knock, midfielder Kevin O'Connor has an ankle injury and striker Farid El Alagui remains sidelined with his knee problem, but Rosler has no new injury worries.
However, the German plans to freshen up his side so midfielder Harry Forrester is in line for a recall while defender Liam Moore could make his debut following his recent loan switch from Leicester.
On-loan Charlton striker Bradley Wright-Phillips lasted just over an hour on his debut and is likely to get another chance from the start.