Mainz lost 1-0 to Bayer Leverkusen in their meeting last week, making it the second consecutive game without a win or a goal. The loss to Leverkusen was Mainz's second loss this campaign and ended a run of three league games without defeat.
Die Nullfünfer sit sixth in the Bundesliga with 10 points from six games. They are six points behind Bayern Munich at the top of the table and will look to win on Sunday and keep pace with the teams at the top end of the table.
Union Berlin beat Arminia Bielefeld 1-0 in their last league game as they ended a three-game winless streak. They enjoyed a stellar outing in their UEFA Europa Conference League clash on Thursday as they beat Maccabi Haifa 3-0.
Die Eisernen sit just a point behind their Sunday hosts in the Bundesliga table in eighth place. They have picked up nine points in the league so far and will be looking to make it 12 on Sunday.
Mainz vs Union Berlin Head-to-Head
There have been 10 meetings between Mainz and Union Berlin in the past. Mainz have won half of those games while Union Berlin have won three of them. The other two games have ended in draws.
The two teams last met in the Bundesliga last season, with Mainz winning the game 1-0.
Mainz Form Guide: L-D-W-W-L
Union Berlin Form Guide: W-L-D-W-D
Mainz vs Union Berlin Team News
Moussa Niakhate and Adam Szalai have both been ruled out with injuries and will play no part in Sunday's game. Alexander Hack is also set to miss the game as he is in isolation after contracting the COVID-19. Aaron Martin is a doubt as he is recovering from a groin injury.
Injured: Moussa Niakhate, Adam Szalai
Doubtful: Aaron Martin
COVID-19: Alexander Hack
Timo Baumgartl has been ruled out with a head injury and is not expected to feature against Mainz. The defender is the only absentee for the visitors.
Injured: Timo Baumgartl
Mainz vs Union Berlin Predicted XI
Mainz Predicted XI (3-4-1-2): Robin Zentner; Silvan Widmer, Stefan Bell, Jeremiah St. Juste; Daniel Brosinski, Leandro Barreiro, Dominik Kohr, Anderson-Lenda Lucoqui; Jean-Paul Boetius; Jonathan Burkardt, Karim Onisiwo
Union Berlin Predicted XI (3-4-1-2): Andreas Luthe; Marvin Friedrich, Robin Knoche, Paul Jaeckel; Christopher Trimmel, Genki Haraguchi, Rani Khedira, Niko Giesselmann; Max Kruse; Taiwo Awoniyi, Andreas Voglsammer
Mainz vs Union Berlin Prediction
Mainz have failed to win any of their last two games and have not scored in either. They are however unbeaten on home turf this campaign and will look to continue that trend.
Union Berlin ended a three-game winless run with back-to-back victories and will be buoyed by that. They are however winless on the road this can and that should continue on Sunday.
Prediction: Mainz 1-1 Union Berlin