RB Leipzig 4 - 0 BK Häcken
(Bruma 35', Matheus Cunha 38', Kampl 50, Augustin 84') Red Bull Arena, Leipzig

With Häacken already midway through their domestic season, Leipzig's new boss Ralf Rangnick (in his second spell as a locum coach with the club) may have been worried that a lack of match sharpness would hinder his side, who are still a month away from their first Bundesliga fixture.

That looked to be the case very early on as Häacken forward Paulinho spurned a glorious headed chance to open the scoring in the ninth minute.

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But soon class began to tell in the scorching heat of the Red Bull Arena. First Jean-Kevin Augustin wasted a very presentable close range chance, before Bruma gave Leipzig a lead that settled any nerves. The Portuguese winger found a pocket of space behind the Häacken backline, gathered a lobbed through ball and blasted home from six yards.

If Bruma's was a tidy finish, better was soon to follow. Cunha, one of a trio of players under 20 signed for over €10 million in the summer, held off a defender as a poor clearance dropped on the edge of the box. The Brazilian, who joined from Swiss club Sion in July, briefly assessed his options before unleashing a dipping drive over Peter Abrahamsson.

With the potential for five more fixtures before even reaching the group stage, the hosts were keen to finish the tie as early as possible and made it three shortly after the break. Augustin turned brilliantly on the halfway line and streaked away from the defense before laying in Kevin Kampl to open his account for the season with a cool sidefoot finish.

Cunha was denied a second by some last-ditch defending from Rasmus Lindgren with 20 minutes remaining as Leipzig pushed for an even more comfortable cushion.

But even if he couldn't get a debut brace, the Brazilian was still bright enough to lay on the fourth for Augustin. Leipzig built up well from the back but Cunha had plenty to do to split the defense. His through ball was beautfiully weighted and left Augustin with a simple finish to wrap things up.

The second leg will take place in Gothenburg next Thursday, August 2. Leipzig will be without midfielder Stefan Ilsanker, who picked up a second booking late on and was sent off.