While the visitors are yet to lose in the top flight this season, the hosts are seeking to claim their fourth league victory in five matches.
Match preview
Eintracht Frankfurt initially found it challenging to juggle their domestic efforts with Champions League action, but they appear to have turned a corner after winning four of their last six games across all competitions.
The Eagles followed up a slender 1-0 Champions League away victory against Marseille with a 3-1 Bundesliga success on the road against Stuttgart in their most recent fixture before the international break.
Oliver Glasner's side have moved up to seventh in the Bundesliga standings and a victory on Saturday could see them climb into the top four if other results were to go their way.
Many teams would welcome the return to home soil, but Frankfurt have struggled at Deutsche Bank Park where they have lost seven league games in 2022 - only Hertha Berlin have lost as many at home during this period. Frankfurt have also failed to score in their last two home matches against Sporting Lisbon and Wolfsburg.
However, last season's Europa League champions have enjoyed recent home meetings against Union Berlin, winning 5-2 in March 2021 before securing a 2-1 victory eight months later.
Union Berlin are enjoying their best-ever start to a Bundesliga season after accumulating 17 points from their first seven fixtures, and they are the only team in the division who remain unbeaten.
Competing in just their fourth top-flight campaign following their promotion from the second tier in 2018-19, the Iron Ones find themselves sitting at the top of the table, two points above Borussia Dortmund in second and five clear of perennial winners Bayern Munich.
Plenty of plaudits are rightly heading Union's way and although former Germany midfielder Michael Ballack believes that they could end the season as champions, Urs Fischer will not get too carried away with his side's strong start to the campaign.
Union Berlin have in fact lost both of their first two Europa League group games this term, suffering 1-0 defeats against both Union SG and Braga, but in the Bundesliga they have put together an impressive 14-game unbeaten run, including results from the backend of last season.
Extending this streak could prove challenging, however, as they have only won two of their last 13 meetings against Saturday's opponents Frankfurt, including the 2-0 home victory in April.
Eintracht Frankfurt Bundesliga form:
D
D
W
W
L
W
Eintracht Frankfurt form (all competitions):
W
W
L
L
W
W
Union Berlin Bundesliga form:
D
W
W
D
W
W
Union Berlin form (all competitions):
W
D
L
W
L
W
Team News
Frankfurt summer signing Jerome Onguene, who is still waiting to make his first appearance for the club, remains sidelined with a groin injury, while fellow defenders Christopher Lenz (hip), Almamy Toure (hamstring) and Buta (knee) are also on the treatment table.
Luca Pellegrini missed the last three games before the international break due to a muscle problem, but the Italian could return to the matchday squad this weekend and will compete with Ansgar Knauff for the left wing-back berth.
Arsenal target Jesper Lindstrom will be hoping to force his way back into the first XI ahead of either Mario Gotze or Daichi Kamada, while Randal Kolo Muani could continue as the lone striker ahead of Rafael Santos Borre.
As for Union Berlin, Danilho Doekhi and Kevin Mohwald are both suffering with muscle injuries, although the former is closing in on a return to action.
Centre-back Paul Jaeckel could return to the starting lineup at the expense of Timo Baumgartl, joining Robin Knoche and Diogo Leite in the back three.
Sheraldo Becker, who has recorded six goals and three assists in seven league games so far this season, is expected to continue in attack alongside Theoson Siebatcheu.
Eintracht Frankfurt possible starting lineup:
Trapp; Tuta, Hasebe, Ndicka; Jakic, Sow, Rode, Pellegrini; Kamada, Gotze; Muani
Union Berlin possible starting lineup:
Ronnow; Jaeckel, Knoche, Leite; Trimmel, Schafer, Khedira, Haberer, Giesselmann; Becker, Siebatcheu
We say: Eintracht Frankfurt 2-2 Union Berlin
An intriguing contest between two strong Bundesliga sides is set to take place on Saturday, and with at least three goals scored in eight of the last nine meetings between the two clubs, plenty of goalmouth action is to be expected.
However, there is little to separate these two sides and an entertaining score draw could be on the cards at Deutsche Bank Park.