Both sides will be aiming to bounce back from defeats on Saturday when they face each other at Broadfield Stadium.
Match preview
After enduring a dismal start to the season under former manager Kevin Betsy, interim boss Lewis Young has steadied the ship since being handed the role last month.
The 33-year-old, who only retired from playing last year after spending seven seasons with Crawley, has won all three of his home matches in League Two in charge so far, which should give himself and his team confidence of beating an out-of-sorts Gillingham on Tuesday.
Indeed, Young was defeated in the league for the first time away to Walsall at the weekend, with Ludwig Francillette's 39th-minute dismissal leaving the visitors in the lurch at 1-1.
However, the Red Devils almost held on for a third successive away draw, but Danny Johnson struck in the second minute of injury-time to end their opponents' unbeaten run under Young at five matches.
Gillingham, meanwhile, will make the relatively short trip to Crawley off the back of four consecutive defeats in League Two.
Saturday's 2-0 defeat away to Newport County saw Neil Harris's side fall into the relegation zone after Colchester United leapfrogged them with a 3-0 win against Doncaster Rovers.
As such, the former Millwall and Cardiff City boss is facing significant pressure in terms of his long-term future at the club, having failed to save them from relegation last season despite his best efforts after being appointed in January earlier this year.
Falling to a fifth consecutive loss against a team only four points and four places above them in the table in the form of Crawley on Tuesday would seriously test Gillingham chairman Paul Scally's patience, especially with an 11-day break until their next league game.
Crawley Town League Two form:
W
W
D
D
W
L
Crawley Town form (all competitions):
D
D
L
L
W
L
Gillingham League Two form:
D
D
L
L
L
L
Gillingham form (all competitions):
L
D
W
L
W
L
Team News
Crawley will be without central defender Francillette after his red card at the weekend, with Tony Craig likely to replace him from the start on Tuesday.
After a mammoth effort from his 10 players for the majority of the late defeat at Walsall, Young could freshen things up by restoring James Tilley to his starting XI.
James Balagizi, who is on loan from Liverpool, is expected to miss out with a groin issue once again.
Harris, meanwhile, could shake things up by making several changes, with Alex MacDonald, Stuart O'Keefe and Scott Kashket pushing for starts in West Sussex.
Having blanked in each of their last four league defeats, the 45-year-old will be desperate to see his struggling side attack with greater fluency as they look to move out of the bottom two positions with a victory.
Crawley Town possible starting lineup:
Balcombe; Francomb, Lynch, Craig, Tsaroulla; Powell, Jenks, Hessenthaler; Nichols, Tilley; Telford
Gillingham possible starting lineup:
Turner; Wright, Ehmer, Baggott; Alexander, Williams, O'Keefe, McKenzie; MacDonald; Kashket, Mandron
We say: Crawley Town 2-1 Gillingham
Crawley have been in good form since Young replaced Betsy in their managerial dugout last month, and we can envisage their winning home run continuing on Tuesday.
Gillingham have lost four league matches in a row without scoring in any of them, and while the latter could end against the division's second weakest defence, the former streak may continue a little longer.