Both sides have recorded 16 wins, eight draws and seven losses this season, so an extra three points for either team would be huge as the race for Champions League football intensifies.
Match preview
Union Berlin's optimistic title dreams may be dead and buried, but the plucky overachievers remain in control of their top-four destiny as they bid to secure Champions League football for the very first time.
Given that Union only gained promotion to the Bundesliga in 2020, it was always going to be difficult for Urs Fischer's side to keep pace with the likes of Bayern Munich and Borussia Dortmund, but they can still finish the season on a high.
Indeed, the Irons Ones find themselves just one point behind third-placed RB Leipzig with three games remaining, while the eight-point gap between them and sixth-placed Bayer Leverkusen means that a top-five finish is all but assured.
Although Union have struggled for consistency in recent weeks - recording one win, two draws and two losses in their last five league outings - Fischer's men will be confident of bouncing back from last weekend's 1-0 defeat at Augsburg.
Not only have Union avoided defeat on home soil in the Bundesliga this term, but they have also conceded just nine goals at Stadion An der Alten Forsterei, helping them achieve the best defensive record in the division.
That said, Freiburg have enjoyed plenty of success on the road of late, chalking up a five-match unbeaten streak away from home thanks to a run of three wins and two draws, including back-to-back victories over Werder Bremen and FC Koln last month.
It is also worth noting that Breisgau-Brasilianer notched three successive wins before suffering a narrow 1-0 defeat to top-four rivals RB Leipzig last time out, so that they will back themselves to return to winning ways this weekend.
When you look at the bigger picture, Freiburg have lost just two of their previous 12 Bundesliga encounters, picking up six victories and four draws to remain in the hunt for Champions League football.
Like Union Berlin, Freiburg have enjoyed a hugely positive season, with head coach Christian Streich - who has managed the club since 2011 - proving that you can achieve success by trusting the process.
Freiburg last qualified for Europe back in 2013-14, finishing third in their Europa League group that season, but Breisgau-Brasilianer will aim to go one better this term as they bid to secure a Champions League spot.
Union Berlin Bundesliga form:
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Union Berlin form (all competitions):
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Freiburg Bundesliga form:
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Freiburg form (all competitions):
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Team News
Urs Fischer can take confidence from the fact that Union Berlin boast an injury-free squad ahead of the run-in, giving the manager multiple options in every department.
Having racked up 10 goals and eight assists this term, Sheraldo Becker will continue in attack alongside Kevin Behrens, who has chipped in with nine goals and three assists across all competitions.
At the opposite end of the pitch, Danilho Doekhi, Robin Knoche and Paul Jaeckel will continue in the backline, with Rani Khedira anchoring the midfield.
As for Freiburg, they will be without midfielder Daniel-Kofi Kyereh for the remainder of the campaign as he continues to recover from an ACL injury, while Philipp Lienhart is a doubt for Saturday's clash due to illness.
There are also question marks over the availability of key winger Ritsu Doan, who missed last weekend's defeat to RB Leipzig after notching seven goals and seven assists this season.
With Doan likely to miss Saturday's showdown, Noah Weisshaupt and Vincenzo Grifo are expected to support the attacking duo of Michael Gregoritsch and Lucas Holer.
Union Berlin possible starting lineup:
Ronnow; Jaeckel, Knoche, Doekhi; Juranovic, Laidouni, Khedira, Haberer, Roussillon; Behrens, Becker
Freiburg possible starting lineup:
Flekken; Kubler, Ginter, Gulde, Gunter; Eggestein, Hofler, Weisshaupt, Grifo; Gregoritsch, Holer
We say: Union Berlin 1-1 Freiburg
Union Berlin and Freiburg look set to play out a cagey draw in the German capital as both sides aim to avoid defeat and maintain their top-four bids.
Although Union have stuttered in recent weeks, Fischer's men are expected to extend their unbeaten run on home soil to 19 matches with a hard-fought draw on Saturday.