"If he gets the chance, then he has to take it and I think he did that today," said BVB head coach Peter Bosz of forward Alexander Isak a few minutes after the final whistle on Tuesday night. The 18-year-old Swede had just made his first start for Borussia Dortmund in their German Cup second-round game in Magdeburg, assisting on the first and scoring the second ina 5-0 rout of their third-division opponents.

Signed for just under €9 million ($10.6 million)  during the last winter break, Isak has tempered the hype around his transfer by quietly getting better over the last nine months. Perhaps he hasn't developed as fast as some other young talents, but both Bosz's statement and Isak's performance suggest this could be the season he starts to make more regular appearances for BVB.

Isak has still only played 110 minutes for Borussia Dortmund. One solid cup performance promises hope but not answers. A goal-scoring debut will no doubt add to the media excitement around this teenager, which started when he joined BVB and there was talk of him being Zlatan Ibrahimovic's heir apparent for Sweden.

Pierre-Emerick Aubameyang is Dortmund's No. 1 forward, but beyond that BVB are thin in leading men. The rest of the attacking figureheads tend to play wider roles and a lot of how Dortmund plays centers around the Gabon striker's style. The emergence of Isak could provide them with some much-needed depth, but expecting too much too soon could be disastrous for a young player who is still getting better.

Three minutes into the game against Magdeburg, Isak failed to take an inviting chance in the box. Just before the break though, he set up BVB's opener with a smart header to a teammate that demonstrated the right kind of awareness in a striker. One minute after the restart, he showed the right kind of coolness as he slotted into the far corner with his weaker foot to make it 2-0.

"We will enjoy him for a long time yet. His development is far from over. As a No. 9 in our system he has to make runs like the one he did for the second goal more often. But he has huge potential," said teammate Nuri Sahin, who added that Isak had taken a huge step forward in preseason.

Dortmund will be hoping that this is the season Isak begins to realizes that potential. Off the back of this performance, there's no reason to think otherwise.