Nuri Sahin confirmed Borussia Dortmund will be without defender Niklas Sule for "several months" after he picked up an ankle injury against Borussia Monchengladbach. 

Sule had missed eight games for Dortmund earlier in the season with a similar issue, and despite only just returning, faces another lengthy spell on the sidelines. 

It provides Sahin with another injury blow, with the BVB boss already without the likes of Waldemar Anton and Julian Brandt. 

Maximilian Beier and Karim Adeyemi are also both doubtful for Dortmund's upcoming Champions League tie against Barcelona on Wednesday. 

"Not so good news, unfortunately," Sahin told a press conference on Sule's injury. "He will be out for several months. He has suffered a serious injury.

"It is the same injury. It is completely unfortunate to injure the same spot. It is very bitter because we needed him.

"He (Sule) had played a good game in Gladbach. It is a bit of a bad luck run for him, but you cannot change that. 

"We have to let the diagnosis sink in. We will play the game tomorrow, and then we will see how we proceed with him." 

Dortmund welcome Barcelona to the Westfalenstadion on Wednesday, with the two teams level on points in the Champions League standings after five games. 

Hansi Flick's side sit third, one place ahead of BVB on goal difference, with both sides knowing a victory this week could be crucial to their hopes of finishing in the top eight. 

But Sahin's side face a tough test against Barcelona, who are the tournament's leading scorers so far with 18 goals. 

Furthermore, Barcelona are unbeaten in their four games against Dortmund in Europe (W2 D2). Across all competitions, this is the most times BVB have faced an opponent in Europe without winning (four).

Dortmund, however, have won four of their first five Champions League matches this season (L1), their best start since 2016-17 (also four wins in five).

Only in 1997-98 have they managed to win five of their first six games in a season, but Sahin is expecting another tough test against the LaLiga leaders. 

"Favourites against Barcelona?" Sahin said. "I don't think there are any favourites tomorrow. It will be two teams on the same level and the form on the day will play a big role."