Marco Reus will miss Borussia Dortmund's Champions League last-16 second leg against Benfica after suffering a hamstring injury in Saturday's 6-2 hammering of Bayer Leverkusen, coach Thomas Tuchel revealed.

The Germany international had been a lively presence and a threat to Leverkusen before he limped off clutching his hamstring just before the break.

Reus has been ravaged by injuries in recent years and his outing on Saturday was only his 11th Bundesliga appearance from a possible 23 this season.

He will now definitely miss the crucial Champions League clash at Signal Iduna Park, with Dortmund 1-0 down from the first leg.

"It's impossible that Reus will play on Wednesday," Tuchel told reporters.

"This is sad news, he's been playing at a high level for weeks. That is a huge loss for us that definitely clouds this victory.

"In our initial sluggish phase, he was the one who was constantly keeping us going, assumed responsibility and was positive."

Although the result was rather one-sided, Tuchel was adamant that Leverkusen made it difficult, with Wendell's free-kick 16 minutes from time making it 3-2 before Dortmund's late flurry.

"It remained a close game because Leverkusen never gave up," he said. "We had to defend diligently in order to avoid the possibility of conceding early chances.

"We always had quick responses to the goals, then we made great goals and were always switched on, even in phases that were not easy.

"It feels like a deserved victory. It is extraordinary for us to shoot six goals in such a match."