Having lost four of his first six Dortmund games - the poorest record since Jurgen Roberin in 2007 - new boss Niko Kovac was hoping for an upturn in form against high-flying Mainz.
A points tally of just 35 after 26 games is Dortmund’s worst in a decade and leaves the Champions League quarter-finalists with slim hopes of European qualification via the league. Nonetheless, a positive start from the hosts encouraged the home faithful, who were in full voice as the visitors withstood the early pressure.
Half an hour ticked by without much consequence, but with half-time looming, Dortmund made the breakthrough.
Perhaps caught in transition, Mainz were unable to deal with a sweeping ball into the box that popped through to Karim Adeyemi, who squared to Maximilian Beier for a simple tap-in.
Only league leaders Bayern Munich had conceded fewer goals than Die Nullfunfer, but just three minutes later, BVB doubled their advantage from a corner as Emre Can nodded in at the back post.
The visitors began the second period on the front foot, firing a succession of shots at the Dortmund goal following the restart.
Gregor Kobel needed to be alert to keep a much-improved Mainz at bay, and having held firm at the back, BVB added a third goal midway through the half.
Once again, it came from a delightful Nico Schlotterbeck corner, with his whipped delivery finding the head of Beier for his brace.
It didn’t take long for the visitors to respond through Paul Nebel, who tucked home after a rather scruffy build-up.
However, that hard-earned Mainz goal came too late to inspire a comeback, with Pascal Gross hitting the post from close range as Dortmund successfully navigated the final minutes.
Eintracht Frankfurt’s Saturday success sees Bo Henriksen’s side drop to fourth in the table, two points clear of fifth-placed Borussia Monchengladbach as they hunt for a first-ever appearance in the Champions League.
Meanwhile, Dortmund’s victory leaves them just four points from sixth, but with four clubs standing between them and a guaranteed European qualification spot, time is running out for Kovač to stage a late revival.
Flashscore Man of the Match: Nico Schlotterbeck (Borussia Dortmund)