Bayer Leverkusen wonderkid Florian Wirtz was forced off with a potential serious knee injury in Sunday's 0-1 defeat against FC Köln.
The 18-year-old went down in pain midway through the first half after being tackled by Luca Kilian and looked distraught as he was carried off the pitch.
At that point, Leverkusen had already been forced to take off Jeremie Frimpong, who was unable to continue after a challenge from Florian Kainz in the opening stage of the game, and to make things even worse for the home side, Odilon Kossounou had to come off at half-time due to muscular problems.
Following a goalless first half with chances at both ends, Kingsley Schindler got the winner for Köln in the 67th minute, just three minutes after coming on. Dejan Ljubicic did well to keep the ball in play before sending in a cross to Schindler, who scored with a volley at the back post.
At the other end of the pitch, second-half substitute Sardar Azmoun squandered a glorious opportunity for Leverkusen 10 minutes later as he failed to connect properly from close range.
With their win, Köln move past Union Berlin into seventh place. Leverkusen are third, five points behind second-placed Borussia Dortmund, who have two games in hand.