In-form Borussia Dortmund forward Karim Adeyemi is set to miss three weeks with a thigh injury, the club announced on Monday.

Adeyemi picked up the injury while setting up a goal for Donyell Malen during Dortmund's 4-1 victory over Hertha Berlin on Sunday, and was helped off the ground in tears.

"Karim Adeyemi tore a muscle fibre during Sunday's game against Hertha Berlin," the club tweeted on Monday. "He will not be available for about three weeks. Get well soon."

Adeyemi, who also scored against Hertha, has been in top form for Dortmund, who sit equal on points on top of the Bundesliga alongside Bayern Munich and Union Berlin.

Adeyemi has three goals and one assist in his past three games.

The Germany striker, who arrived from Red Bull Salzburg in the summer, looks set to miss games against Hoffenheim, RB Leipzig and Schalke.

A three-week absence would also mean Adeyemi is ruled out of the return leg of Dortmund's Champions League tie with Chelsea in London.

Dortmund hold a 1-0 advantage after the first leg, in which Adeyemi scored the only goal.