Borussia Dortmund's Shinji Kagawa in action with Magdeburg's Nico Hammann during DFB Cup Second Round in Magdeburg, Germany, Oct 24, 2017. [Photo/Agencies]

BERLIN — Defending champion Borussia Dortmund used the German Cup to bounce back from a recent dip in form by racking up a 5-0 win at third-division Magdeburg in the second round on Tuesday.

Dortmund, which hadn't won in three games across all competitions, attacked from the start with Maximilian Philipp striking the post and Alexander Isak drawing a good save from Alexander Brunst on the rebound.

The 17-year-old Isak, who was making his competitive debut for Dortmund, had better luck later on. The Swedish forward set up Gonzalo Castro for the opening goal before the break, and then sent a shot through Brunst's legs to make it 2-0 just two minutes after the re-start.

A penalty from Andrey Yarmolenko wrapped up the result with a quarter of an hour remaining. Shinji Kagawa helped complete the rout, crossing for Marc Bartra to score with a header before claiming a goal for himself after combining well with Philipp.

"An early goal would have been more helpful, but even so we showed who the higher level team was," said midfielder Nuri Sahin, who also rejected any suggestion of a Dortmund crisis. "There was none. We're leading the table in the Bundesliga and are now comfortably through (in the German Cup)."

Union, which plays in Germany's second division, was pushing for an equalizer to force extra time with the score at 2-1 until a penalty from Wendell sealed the home side's win in the 89th minute.

Charles Aranguiz gave the score a flattering look by sending a perfect free kick inside the left post in injury time. Union midfielder Stephan Fuerstner was sent off with his second yellow card for the foul that led to the free kick.

Mainz needed extra time to beat second-tier Holstein Kiel 3-2.

Earlier, Borussia Moenchengladbach edged second-division leader Fortuna Duesseldorf 1-0, Schalke won 3-1 at third-tier SV Wehen Wiesbaden, and third-division Paderborn upset second-tier Bochum 2-0.

AP