Pierre-Emerick Aubameyang believes Marco Reus' return from injury is crucial to kick-start Borussia Dortmund's season.

The Germany international has been out since the end of the 2015-16 campaign with a groin injury that forced him to miss Euro 2016, but he returned to training last week.

And with Reus soon to be back on the pitch, Aubameyang has had words of encouragement for his team-mate, who he says has an important role in a Dortmund side struggling to keep pace with Bundesliga champions Bayern Munich.

"It's a good sign that he's back training again," the Gabon international told the league's official website. "We need Marco.

"I sent him a message not long ago, telling him to keep believing in himself. I also told him personally how important his return is for the whole team.

"Not just me, but the team, the club – everybody's standing behind him. We all hope he'll be back on the field soon."

Dortmund lie sixth in the table with eight games played, trailing Bayern by six points at this early stage.