Borussia Dortmund will be without Karim Adeyemi and Julien Duranville for several weeks after they were injured in Tuesday's 7-1 Champions League victory over Celtic, coach Nuri Sahin has revealed.

The Ruhr valley club earned their biggest-ever European win in midweek, crushing the Scottish champions with Germany international Adeyemi scoring a hat-trick before being taken off with a muscle injury and replaced by 18-year-old Belgium international Duranville.

Duranville later sustained an injury of his own and both players will be absent until late November, missing Saturday's trip to Union Berlin as well as seven further games.

"We will be without Karim and Julien for some time. They are expected to be back after the international break in mid-November," Sahin said at Friday's pre-match press conference.

He added Giovanni Reyna, sidelined since last month, will also delay his comeback after suffering a setback in his recovery.

Dortmund, who are currently fifth in the Bundesliga on 10 points, three behind leaders Bayern, are seeking their first pair of back-to-back league wins under Sahin at Union.

BVB have struggled for consistency so far, suffering a 5-1 defeat at Stuttgart two weeks ago then bouncing back with a 4-2 win over Bochum and cruising past Celtic in Europe.

"When something is supposed to grow together you need time," Sahin said. "Every day in this development is important. I am not looking for excuses.

"I know well how to rank the Celtic game. It is not that we are hugging each other saying 'we are the coolest' because we won 7-1.

"We are expected to deliver such performances every three days and if we win on Saturday then the world may look a bit cooler."