Sven Bender is injured and could be repaced by Sebastian Kehl in defensive midfield.
If Kehl himself cannot recover in time, the more attack-minded Moritz Leitner could get a chance to start alongside Ilkay Gündogan.
Kevin Großkreutz, Ivan Perisic and Jakub Blaszczykowski compete for a spot on the wing.
Manager Klopp will come up against his former employers in this game.
Mainz have been in good form lately and should not have lost too much confidence after their loss at Hamburg last weekend.
Dortmund have been in solid form as well and their Champions League performances have given the team a lot of confidence to take into the domestic campaign. It remains to be seen how tired some players will be after a trip to Amsterdam though.
Expect Dortmund to dominate the game from the outset and Mainz to try to hit them on the break.
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