These two teams are next to each other in the Eastern Conference table coming into the match, with the hosts in 12th and their visitors in 13th, although Chicago have played a game fewer than United.
Match preview
Ezra Hendrickson's Chicago Fire have had a difficult start to the 2023 campaign, as their season opened with a 0-0 draw at home to New York City, a 1-0 reverse away at Philadelphia Union and a thrilling 3-3 tie with Cincinnati.
Last time out the Fire got their first victory of the term with an impressive 3-2 success away at Inter Miami, with the visitors racing into a 2-0 lead through Chris Mueller and Carlos Teran before being pegged back to 2-2, only for Kei Kamara to win the match for the Illinois outfit in the 91st minute.
Five points from their opening four encounters has Chicago in 12th place coming into this weekend's match and they will hope to use that triumph over Miami as a springboard for a run of results that will take them up the table - a second successive win on Sunday may lift Hendrickson's team into the playoff places, depending on other results.
The Fire are hoping to improve on 2022's bottom-half finish and it is a good early-season sign that they are beginning to spread goals around the team as a way to make up for Jhon Duran's move to Aston Villa in January - five different players have already netted this campaign, which shows that they are not overly reliant on any one individual.
Moreover, Chicago have scored three times in each of their last two games and have the chance on Sunday to do so in three successive matches for only the second time in the last 10 years, having also managed it in 2021.
Kei Kamara also continues to be a stalwart in the MLS as his stoppage-time winner last weekend was his 145th in US league matches, and he will confident of netting again against a side that has conceded more than once in four of their first five matches this term - only the third time DC United have suffered that fate in their history.
Wayne Rooney has not had the start to the season that he would have wanted at DC United with the Washington outfit labouring in the opening weeks of 2023, as a 3-2 success over Toronto on day one was followed by just a solitary point from the next four matches, which came in a 1-1 draw at home to Orlando City.
In their last match, United were beaten 2-1 at home by New England Revolution as Christian Benteke's first-half strike was cancelled out in the 63rd minute by Gustavo Bou before the hosts suffered late disappointment when Noel Buck won the game for the visitors with two minutes to play.
Rooney's side desperately need to turn their season around or the Premier League legend's job will start to come under threat even at this early stage of the campaign.
The meeting with Chicago already feels like a pivotal one as a win could lift them into the playoff places and give them something to build on, but a defeat and United may end the weekend bottom of the division.
One success story for the Black-and-Red so far this season has been the form of Belgian striker Benteke, who joined in the summer from Crystal Palace.
The former Villa and Liverpool forward has three goals in his first five matches, including an equaliser in their only win of 2023 against Toronto, and he will be hoping to continue his fine scoring streak against the Fire on Sunday.
Fixtures between Chicago and DC have been evenly matched in recent years, with each winning twice in the previous five encounters.
That said, DC United were the only team Hendrickson's side did the double over last year, triumphing 1-0 at Soldier Field and 2-0 away, and they could keep three successive clean sheets in this fixture for the first time since 2003 this weekend.
Chicago Fire Major League Soccer form:
DC United Major League Soccer form:
Team News
The hosts will be without their influential Swiss midfielder Xherdan Shaqiri against United as he is struggling with a muscle injury, so Saturday's goalscorer Mueller will keep his place in the starting 11 on the left flank.
Chicago are likely to otherwise be unchanged from the win over Miami with Brian Gutierrez supporting Kacper Przybylko upfront, although Kei Kamara is pushing for a start after netting the winner last time out.
Javier Casas and Alonso Aceves may also be in line to start against the Red-and-Black to add extra steel and width to the side after making appearances from the bench in their last game.
DC United's Martin Rodriguez is missing after rupturing his cruciate ligament so Jackson Hopkins will start on the left of a four-man midfield in a 4-4-2 system.
Centre-back Brendan Hines-Ike is out with a foot injury so Derrick Williams will partner club captain Steve Birnbaum at the heart of United's defence.
Chicago Fire possible starting lineup:
Brady; Souquet, Teran, Czichos, Dean; Gimenez, Casas; Haile-Selassie, Gutierrez, Mueller; Pryzybylko
DC United possible starting lineup:
Miller; Durkin, Birnbaum, Williams, Greene; Ruan, Canouse, Klich, Hopkins; Ku-DiPietro, Benteke
We say: Chicago Fire 2-1 DC United
The hosts will be boosted by their victory last time out and will be confident of recording back-to-back wins at home against Wayne Rooney's struggling side, but another clean sheet may elude them due to Benteke's form.
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