The visitors head into the encounter one point behind their forthcoming opponents with a game in hand, and victory for either would be enough to take them ahead of Orlando City in seventh spot.
Match preview
Having finished rock-bottom of the overall MLS table last season, DC United will be hoping for much better things from their manager Wayne Rooney this time around.
The England legendary striker departed Derby County to head to the American capital last July, but he was unable to turn the club's fortunes around, meaning they failed to qualify for the play-offs for the third consecutive campaign.
However, from their opening 15 league games, Rooney's side are only eight points shy of their entire points haul from 34 matches last time out, which has put them within the cusp of the automatic play-off qualification spots in the table.
That said, after pulling off an impressive 3-0 win against LA Galaxy, Rooney and his players will be determined to bounce back after losing 2-1 to Toronto across the weekend, with former Liverpool striker Christian Benteke's second goal in two matches ultimately coming in vein as a late response to their opponents' strikes either side of half-time.
Montreal, meanwhile, registered their best ever league placing when finishing second in the Eastern Conference last season, with former head coach Wilfried Nancy guiding L'Impact to the last eight of the play-offs for the third time since they joined the MLS in 2012.
However, they were defeated 3-1 by New York City FC, with Hernan Losada subsequently chosen to lead from Montreal's managerial dugout after Nancy departed for Columbus Crew.
Le CFM have proven to be a mixed bag under their new manager thus far, winning six and drawing eight of their league matches, with the fact that their goal difference is considerably worse than anyone else's in the Eastern Conference suggesting they have plenty to improve on throughout the coming months.
Indeed, successive defeats from their last two away trips have increased the pressure on Losada ahead of his side's trip to Washington this week, with the 41-year-old perhaps set to focus on tightening up his defence first and foremost.
DC United Major League Soccer form:
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CF Montreal Major League Soccer form:
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Team News
DC United appear set to remain without Ruan, Mohanad Jeahze, Nigel Robertha and Martin Rodriguez due to injury, but Steve Bimbaum returned from a hip injury to be included in their matchday squad for the defeat against Toronto on Sunday.
Taxiarchis Fountas and Cristian Dajome could come into the hosts' starting XI after only being used from the bench at the weekend, with former Leeds United midfielder Mateusz Klich potentially dropping to the bench as a result.
Montreal, meanwhile, will travel without Mason Toye and Samuel Piette due to knee and groin issues respectively, with Losada potentially considering naming the same team that defeated Inter Miami 1-0 on Sunday.
Chinonso Offor will almost certainly lead the line after scoring the crucial winner for his side, with the likes of Rudy Camacho and Ahmed Hamdi set to provide options from the bench once again.
DC United possible starting lineup:
Miller; Palsson, Williams, Pines; Durkin, Canouse, O'Brien, Samake; Fountas, Dajome; Benteke
CF Montreal possible starting lineup:
Sirois; Waterman, Campbell, Corbo; Herrera, Choiniere, Wanyama, Lappalainen; Duke; Ibrahim, Offor
We say: DC United 2-1 CF Montreal
Montreal have struggled away from home in recent outings, and we believe DC United have enough about on present form to inflict a third consecutive league defeat on the road for their opponents.
Rooney will be pleased to see his star striker Benteke getting back among the goals, and the target man could prove to be a key figure once again on Wednesday.
How to watch
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