Bayern Munich will be without wingers Kingsley Coman and Serge Gnabry for Wednesday's Champions League quarter-final second leg at home to Arsenal.
France's Coman suffered yet another leg muscle injury with no Cologne player near in Saturday's 2-0 Bundesliga win and had to be helped from the pitch by two physios. Gnabry was ruled out of the game with his own muscle pull.
Manuel Neuer and Leroy Sané were rested against Cologne after recent injuries but are expected to return against the Gunners, with the tie locked at 2-2.
"Two will hopefully be back and two seemingly definitely out," Bayern coach Thomas Tuchel told Sky.
A club statement later read: "Kingsley Coman will be out of action for FC Bayern for several weeks after the forward suffered an injury in his right adductor muscle."
The Champions League is Bayern's last chance at silverware this season, with Bayer Leverkusen on the brink of ending the Bavarians' 11-year reign as Bundesliga champions.
Portugal left back Raphaël Guerreiro scored and played in midfield against Cologne and could be an option on the wing against Arsenal.