They were still top, still in charge of their own destiny and, lest we forget amid the jitters, still way ahead of schedule or expectation. It didn’t feel like that, though, after three weeks in which a seven-point lead over Bayern Munich had disappeared, the team had exited the DfB Pokal and slid to the brink of following suit in the Champions League.

For Borussia Dortmund the final insult was the prospect of former coach Peter Bosz, returning on Sunday with his improving Bayer Leverkusen, “getting the chance to totally ruin another Dortmund season,” in the words of German journalist Lars Pollmann. Yet while much focus was on the Dutchman, whose new side arrived on the crest of 13 goals in their last four Bundesliga games (at least to some extent echoing his long-forgotten, excellent start at Westfalen 18 months ago), the sense of deja vu eventually came from elsewhere.

“They were better than us,” said Lucien Favre, with customary frankness. He was right. When Dan-Axel Zagadou sidefooted in a corner to give Dortmund a first-half lead, it followed half an hour in which they barely got the ball out of their own half. “That,” sporting director Michael Zorc said with some understatement, “was of course not the plan. At home, you want to attack and you want to dominate.”

It was, however, almost comforting in that it was a return to the first template of early season. As the results mount up the detail fades, but much of Dortmund’s success this term has been built on phenomenal efficiency. If we wind it back to the very first game of the season, where the record books tell us that BVB impressively rolled over a fellow top-four hopeful in Leizpig, closer examination – or better memory – tells us they spent long periods of the game soaking up pressure before punishing the visitors on the break. Favre’s post-match assessment after his Bundesliga debut with the club that day? “They were the better team.” Plus ça change.

So while, when Paco Alcácer had one ruled out for a fractional offside which would have put Dortmund 4-1 up and Jonathan Tah pulled one back for the visitors to make it 3-2 shortly afterwards, it may have felt like a near-rerun of the previous home game with Hoffenheim, where they shelled that 3-0 lead, it was actually a more common situation. A situation that Dortmund know how to cope with.

They just had to remind themselves that they could do so after five without a win in all competitions, but that is what they eventually did. The defensive holes that they learned to cover, with a mix of dogged collective application and with that dizzyingly-sprinkled stardust in the final third, are still there. So is Roman Bürki. He again made key saves at 3-1, from Leon Bailey and Lucas Alario.

One wonders what Bosz thinks of all this. He has largely kept his own counsel, even if his goalkeeper Lukas Hradecky had said that returning to Westfalen and winning would be “extra sweet” for the coach. If he was notoriously inflexible with his tactics – and the early signs at Leverkusen are that he has learned a lesson or two – Bosz had bad luck as well. Bürki suffered the worst form of his Dortmund career under him (unnerved by the coach’s haphazard defensive set-up, some might argue), and the coach pointed out in his Friday pre-match press conference that he was never able to call on Marco Reus, who was recovering from a knee injury during his spell at the helm.

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With the Dortmund captain being nursed back to health after a thigh strain, missing a fourth straight game here, Bosz got a bit of that luck back, as he acknowledged before the game. His goals and his talismanic presence are missed and Zorc mused that it was “important for the players to show themselves they could do it without him.” They hope that state won’t last much longer, and Zorc believes they might have him back to face Augsburg on Friday.

If it provestoo soon, there’s no need to panic. The resolve here was clear, even if the fluency wasn’t always so evident. After a thoroughly deserved equaliser for Leverkusen by Kevin Volland, Dortmund simply went straight back up the other end for Jadon Sancho to put them back in front with a superb volley. That passage of play, responding to a setback decisively, gave them the confidence toget what they needed from the game.

#JS7 | In the Blink of an Eye ✨ pic.twitter.com/w7TrajSEDs — Football on BT Sport (@btsportfootball) February 25, 2019

“We made one or two mistakes too many to survive here,” lamented the visitors’ Julian Brandt, underlining Leverkusen’s – and Bosz’s – standards, and tipping his hat to Dortmund’s qualities. Yet what Favre and company had shown was that mistakes happen. It’s how you react to them that counts. They might just have rediscovered the thread of their successful season, even with its fraying.

Talking points

• “I’ve played against better Bayerns,” said Hertha defender Niklas Stark after his side’s 1-0 defeat at the Allianz Arena, and it’s a common feeling this term. Yet now there is no doubt; they’re looming over Dortmund in a way that they hadn’t so far this season. The gritty draw at Liverpool was followed by a rare clean sheet , their first in the Bundesliga in 2019. If winning goalscorer Javi Martínez was key in both matches, so was Niko Kovac. Bayern really look like his side now. It’s “a new minimalism”, in the words of Süddeutsche Zeitung’s Maik Rosner.

Javi Martínez is congratulated by Serge Gnabry and David Alaba after scoring Bayern’s winning goal. Photograph: Pixathlon/Rex

• Bad vibes at Schalke. Die Königsblauen were hammered 3-0 at Mainz (Karim Onisiwo scored twice), with their players feeling the full ire of their travelling supporters, and news followed shortly afterwards that sporting director Christian Heidel would step down at the season’s end (or sooner, if they find a suitable replacement). The 55-year-old has received credit for walking away from any potential compensation, but his exit is the logical end point to a string of signings that haven’t worked and the club’s worst points tally at this point in the season since 82-83, when they eventually went down.

• Borussia Mönchengladbach are losing touch with the top two. Having won their first nine Bundesliga games at fortress Borussia-Park, they’ve now lost two in a row there – scoring none, conceding six – after Saturday’s reverse to Wolfsburg. They certainly had their chances, especially before Yannick Gerhardt gave the visitors the lead, before the visitors took it away from them with an Admir Mehmedi double, with “incredible efficiency”, as Gladbach sporting director Max Eberl put it. Uli Hoeness denied targeting Eberl for the equivalent role at Bayern during Sport 1’s Dopplepass.

• After Augsburg’s “frighteningly weak” (as described by Kicker) performance in a 5-1 loss at Freiburg, sporting director Stefan Reuter denied that he planned to give coach Manuel Baum the chop. Just way less emphatically than he did three weeks ago. Captain Daniel Baier breaking ranks to say his team need to “change everything” doesn’t help either.