Borussia Dortmund staged a convincing 4-2 comeback win over VfL Bochum in the Bundesliga on Friday, thanks to a brace from Serhou Guirassy, but coach Nuri Sahin insists his side must continue to improve defensively to avoid further setbacks.

Serhou Guirassy scored twice and won a penalty as Borussia Dortmund overturned a two-goal deficit to beat local rival Bochum 4-2 in the Bundesliga ahead of facing Celtic in the Champions League next week.

On a torrid night in Westphalia, Borussia Dortmund were able to bounce back from their 5-1 defeat against VfB Stuttgart last time out with a 4-2 triumph over neighbours VfL Bochum