A win for Bremen, meanwhile, would ease any relegation concerns this season by taking them eight points clear of their forthcoming opponents in the table.
Having gained promotion to the Bundesliga last season, survival was always going to be a tough ask for Uwe Neuhaus's Arminia side.
The 61-year-old has worked wonders to keep them out of the relegation zone for most of the season, but last weekend's 3-1 defeat at the hands of FC Koln saw the victors leapfrog their opponents in the table.
Markus Gisdol's side had been boosted by the additions of Max Meyer and Emmanuel Bonaventure earlier in the week, showcasing the difference in budgets between the fellow strugglers. However, it was a loanee who proved the difference on the day, with Marius Wolf twice pouncing on rebounds to provide Koln with a strong lead heading into the half-time interval.
Elvis Rexhbecaj's decisive finish with a little under half an hour remaining all but ended the tie as a contest, with Sergio Cordova's late effort ultimately providing to be little more than a consolation goal. Sunday's match against Bremen is close to being a a must-win one for Arminia, with it representing a perfect opportunity to reel the pack of five teams above them in.
Bremen, meanwhile, were disappointed to only draw 1-1 at home against bottom-of-the-table Schalke 04.
In fairness, the Bundesliga's crisis club have undoubtedly improved since Christian Gross took over as manager, with Omar Mascarell capping a fine team move in the first half after Matthew Hoppe had earlier spurned a golden opportunity for the visitors. Armine Harit was unsurprisingly at the heart of almost everything positive they mustered.
However, Florian Kohfeldt made three substitutions at half time, with two of them combining to equalise when Milot Rashica teed up Kevin Mohwald. It was a tale of two halves with Bremen dominating the second half, with Maximilian Eggestein and his teammates believing they had found a winner only for Theodor Gebre Selassie to correctly adjudged to have been offside in the build-up.
Only Bayern Munich have won more DFB-Pokals than Bremen's impressive tally of six historical triumphs in German's major cup, meanwhile, with Kohfeldt keeping his side's hopes alive in that competition with a 2-0 win over Greuther Furth in midweek. Another strike from Mohwald was added to by Felix Agu in a comfortable victory, which should help boost confidence ahead of the trip to Bielefeld.
Arminia Bielefeld Bundesliga form: LWDWLL
Werder Bremen Bundesliga form: LDWLWD
Werder Bremen form (all competitions): DWLWDW
Cordova is likely to start having made a good impact from the substitutes' bench in the defeat in Cologne.
Kohfeldt will be tempted to start Mohwald and Rashica after their excellent introductions against Schalke last weekend.
Arminia Bielefeld possible starting lineup:
Ortega; Brunner, Van der Hoorn, Nilsson, Laursen; Doan, Kunze, Hartel, Yabo; Cordova, Klos
Werder Bremen possible starting lineup:
Pavlenka; Veljkovic, Toprak, Friedl; Gebre Selassie, Bittencourt, Eggestein, Mohwald, Agu; Rashica, Sargent
We say: Arminia Bielefeld 1-1 Werder Bremen
Bremen have drawn six of their 19 games 1-1 this season, so it would be little surprise to see the same scoreline here with both sides perhaps more desperate not to lose than win.
Arminia will need to improve on their performance at Koln last weekend, though, with the likes of Rashica and Joshua Sargent capable of punishing them in transition.