The Bundesliga champions settled for a goalless draw against Stuttgart in the Bundesliga on Saturday, and they lost Nordi Mukiele to a thigh injury at the start of the second half.
The Frenchman is not expected to make a full recovery until after the November international break, and he joins Amine Adli (broken leg) and Jeanuel Belocian (foot) on the sidelines for now.
However, Alonso is confident that Martin Terrier will be back from the knock that kept him out of Friday's game, and the winger's return would allow Jeremie Frimpong to revert to right wing-back duties in place of Mukiele.
Frimpong formed an attacking trident with Victor Boniface and the much-coveted Florian Wirtz on Friday, and the latter two should welcome either Terrier or Jonas Hofmann back to the final third at Anfield.
Granit Xhaka also returns to a ground where he suffered many embarrassments in his Arsenal days, but Robert Andrich could drop out for Aleix Garcia, who has made more line-breaking passes into the final third than any other midfielder in the 2024-25 Champions League.
A reported transfer target for Liverpool, Piero Hincapie starts in a familiar defensive setup with Jonathan Tah and Edmond Tapsoba in front of Lukas Hradecky.
Bayer Leverkusen possible starting lineup:
Hradecky; Tapsoba, Tah, Hincapie; Frimpong, Xhaka, Garcia, Grimaldo; Terrier, Wirtz; Boniface