On the flipside, the visitors can seal their spot in the knockout stages by winning at Stadion An der Alten Forsterei.
Match preview
After losing their first two matches in the Europa League this season, Union Berlin's place in the competition was hanging on perilously by a thread.
However, successive 1-0 wins against Malmo have moved Urs Fischer's side one point behind Braga ahead of their meeting on Thursday, meaning a home win would keep their destiny in their own hands ahead of facing group leaders Union Saint-Gilloise in Belgium next week.
Domestically, Fischer's side remain top of the Bundesliga after 11 matches despite falling to a disappointing 2-1 defeat away to VfL Bochum at the weekend. Given that it was the top side versus the bottom team in Germany's top flight heading into the encounter, few people would have seen that result coming.
However, advancing to the knockout stages of the Europa League while challenging for a top four position would be considered an incredible achievement from Fischer, who continues to take Union Berlin on an upwards trajectory. In all likelihood they will need to beat Braga this week in order to achieve the former objective, though.
Indeed, given that Braga host Group D's whipping boys Malmo next week, head coach Artur Jorge will almost certainly be viewing his team's trip to Berlin this week as a must not lose match as opposed to must win.
A draw would be perfectly adequate given that it would mean following that up with a victory against Malmo next week would guarantee them at least second spot in the group, and a place in the knockout stages of the Europa League for the fourth successive season.
That would be no mean feat for a club the size of Braga, who continue to punch above their weight both domestically and on the European stage. Indeed, they have never won the Portuguese Primeira Liga and have only once finished second, but that is where they find themselves in the table after 10 games this season.
However, Jorge - who only became head coach during the summer after a brief spell in charge in 2020 - will be keeping his players' collective feet on the ground, especially as a defeat on Thursday could mean falling short of one of his main aims despite a strong start to his tenure.
Union Berlin Europa League form:
L
L
W
W
Union Berlin form (all competitions):
W
W
W
W
W
L
Braga Europa League form:
W
W
L
D
Braga form (all competitions):
W
L
L
L
D
W
Team News
Union Berlin will be without Andras Schafter due to suspension after the Hungary midfielder was sent off against Malmo earlier in the competition.
Otherwise, Fischer appears to have a fully fit squad to choose from, with Julian Ryerson and Genki Haraguchi likely to be restored to the starting XI after only being named on the bench in Bochum at the weekend.
Likewise, Braga have no known injury concerns at present, meaning Jorge can name the strongest side which he feels capable of picking up a positive result in Berlin.
Club captain Ricardo Horta, who has made five caps for Portugal, will lead the team out from the left flank.
Union Berlin possible starting lineup:
Ronnow; Jaeckel, Knoche, Leite; Trimmel, Haraguchi, Khedira, Haberer, Ryerson; Siebatcheu, Becker
Braga possible starting lineup:
Matheus; Fabiano, Tormena, Niakate, Sequeira; Gomes, Al-Musrati, A Horta, R Horta; Oliveira, Ruiz
We say: Union Berlin 1-0 Braga
We expect a very cagey affair at Stadion An der Alten Forsterei, with both teams knowing the significance of this fixture in terms of progressing to the knockout stages.
Which ever team scores first will feel confident of getting the result they need, and we are backing Union Berlin to do so and hold on for a vital victory.