The Irons Ones were played off the park in the reverse fixture nearly six months ago when they suffered a heavy 5-0 away defeat to Die Werkself.
Match preview
Four years after securing promotion to the Bundesliga for the first time in their history, few would have imagined Union Berlin challenging for a top-four finish this season, let alone being in with a shout of lifting the title heading into the remaining five fixtures.
Defeat to current leaders Borussia Dortmund and dropping two points at home to Bochum VfL put a major dent in their title hopes, but last weekend's slender 1-0 win over Borussia Monchengladbach, courtesy of a second-half strike from Sheraldo Becker, has provided them with a glimmer of hope.
Urs Fischer's side currently sit third in the table with 55 points from 29 games, four points clear of RB Leipzig in fifth and five points adrift of Dortmund at the summit.
Union Berlin are one of only two Bundesliga sides, along with Bayern Munich, who are yet to lose on home soil this season, winning nine and drawing five of their 14 matches at the Stadion An der Alten Forsterei. The Iron Ones have also conceded just nine goals at home, fewer than any other team in the division.
Victory on Saturday would see Union Berlin surpass their record top-flight points total from last season (57), but success against Leverkusen could prove challenging as they have won only one of their 10 competitive meetings with Die Werkself - a narrow 1-0 home win in January 2021.
Bayer Leverkusen extended their impressive unbeaten run across all competitions to 13 matches when they ran out 2-0 winners at home to Leipzig last weekend.
Adam Hlozek netted his second goal in as many games to open the scoring on the stroke of half time before substitute Nadiem Amiri converted from the penalty spot four minutes from time to secure maximum points.
Xavi Alonso has worked wonders with Leverkusen since taking the reins in October, winning 13 and drawing three of his 21 league games in charge, which has helped Die Werkself climb from the bottom half of the table up to sixth place and in contention to qualify for Europe.
Leverkusen are also through to the semi-finals of the Europa League where they will face Roma over two legs, but they must first turn their attention to Saturday's Bundesliga trip to Union Berlin, who they thrashed 5-0 on home soil earlier this season.
Die Werkself have failed to win their last two visits to Union Berlin, but an unbeaten run of five away matches in which they have scored 10 goals in the process will provide them with confidence to claim a positive result in the German capital.
Union Berlin Bundesliga form:
D
W
W
L
D
W
Union Berlin form (all competitions):
W
W
L
L
D
W
Bayer Leverkusen Bundesliga form:
W
W
W
W
D
W
Bayer Leverkusen form (all competitions):
W
W
D
D
W
W
Team News
Union Berlin forward Kevin Behrens will serve a one-match suspension after picking up his fifth yellow card of the season last weekend, while Andras Schafer is doubtful with an ankle injury and will be assessed ahead of kickoff.
Jordan Siebatcheu has not scored since February but he is the most likely candidate to replace Behrens and join top scorer Sheraldo Becker up front.
Paul Jaeckel is available for selection after serving a one-game ban last time out and the centre-back will be looking to return to the first XI at the expense of either Diogo Leite or Danilho Doekhi.
As for Leverkusen, Patrick Schick and Andrey Lunev are both ruled out with respective groin and back injuries, while Nadiem Amiri will serve a one-game suspension due to an accumulation of yellow cards, picking up his fifth last weekend after jumping into the away end to celebrate his goal.
Edmond Tapsoba, Exequiel Palacios both missed the win over Leipzig with muscle problems, as did Florian Wirtz due to illness, but the trio are fit to return on Saturday and could be selected from the start.
The potential inclusion of centre-back Tapsoba could see Mitchel Bakker drop to the substitutes' bench and Piero Hincapie move up from centre-back to left wing-back, while Wirtz will likely replace Amine Adli in an advanced midfield role.
Union Berlin possible starting lineup:
Ronnow; Doekhi, Knoche, Leite; Juranovic, Laidouni, Khedira, Haberer, Roussillon; Becker, Siebatcheu
Bayer Leverkusen possible starting lineup:
Hradecky; Kossounou, Tah, Tapsoba; Frimpong, Andrich, Palacios, Hincapie; Diaby, Wirtz; Hlozek
We say: Union Berlin 1-2 Bayer Leverkusen
Union Berlin (11) and Leverkusen (15) have conceded the fewest Bundesliga goals since the turn of the year, but considering this fixture has seen both teams score in five of the last seven meetings, an entertaining contest could be on the cards on Saturday.