Borussia Dortmund maintained their perfect start to their Champions League campaign with a comprehensive 4-0 victory over Galatasaray in Group D.

Dortmund have been struggling for form in the Bundesliga but three first-half goals, including two from Pierre-Emerick Aubameyang and another from the excellent Marco Reus, put the Germans out of sight before Adrian Ramos added a fourth late on.

The victory means Jurgen Klopp's team are three points clear at the top of the group with home matches against Galatasaray and Anderlecht to come either side of a visit to Arsenal.

In contrast, Galatasaray's hopes of qualification are hanging by a thread as they sit bottom of the group and five points adrift of second.

Reus has been finding his rhythm again of late and the German winger was at his scintillating best at the Turk Telecom Arena, scoring one and setting up another in an impressive individual display.

It was the 25-year-old's pin-point cross that set up Aubameyang to tap home his first goal after six minutes and the dynamic striker added another from close range 12 minutes later to put Dortmund firmly in command.

The visitors were starting to enjoy themselves and Aubemeyang could have sealed his hat-trick on the half-hour as he diverted Henrikh Mkhitaryan's ball onto the post.

Shinji Kagawa also went close for the visitors but it was Reus who did finally add a third with the goal of the night shortly before half-time.

Picking up the ball on the right, he unleashed a dipping, long-range shot that flew over the head of Fernando Muslera and into the top of the net, prompting applause even from the home supporters.

Galatasaray enjoyed more possession in the second half as Dortmund eased off in the latter stages but there was still time for Ramos to notch a fourth late on.

The Colombian had been on the field less than a minute but made an instant impact, applying a composed finish to round off a convincing win and put Dortmund within touching distance of the knock-out stages.