Bild: Borussia Dortmund's Karim Adeyemi could be out for up to four weeks

After Borussia Dortmund's stellar performance against Celtic in the Champions League, the main topic of conversation has been Karim Adeyemi and his contribution to the game. The German attacker's three goals were the main catalyst for this absolute route as Adeyemi struck the figure of a man on a mission to put in a showing the fans would not forget anytime soon.

Alas, elation has quickly turned to dismay as the player has picked up an injury that will likely keep him off the pitch for some time to come. During the early moments of the second half, the player collapsed to the ground after landing awkwardly while trying to win an aerial duel.

According to Bild, the injury is a torn muscle fiber in his thigh. Adeyemi will likely be sidelined for up to four weeks.

While the length of time Adeyemi will be out is not necessarily season-altering (especially if players waiting in the wings step up), it is a disappointing blow for Adeyemi who is no stranger to these sorts of muscular concerns. It will also be a bitter blow for Adeyemi after the strong start to the season that he's had. Dortmund's in-form wide man currently has five goals and three assists across seven appearances in the Bundesliga and Champions League combined.

With Adeyemi out for most of October, he will be missing key clashes against Real Madrid in the Champions League as well as Union Berlin and VFL Wolfsburg in the Bundesliga. It will be up to players such as Jamie Gittens (who has also had a strong season), Donyell Malen, and Julien Duranville to step up and fill the gap left by Adeyemi's injury on the wing. It could give one of these players a stretch of games to really push for a starting position alongside Adeyemi once he returns from his injury layoff.