It ended on a Tuesday night, 21 February. The looks that the Bayer Leverkusen players exchanged on the turf at the final whistle – at least, of those that could bear to make eye contact – after a spirited but vain second-half rally against Atlético Madrid in the Champions League, spelled it loud and clear. It was all over; not only for Leverkusen in Europe but for their coach Roger Schmidt’s tenure.

The official end came in a club statement on Sunday morning, backsides still red raw from a 6-2 spanking at Borussia Dortmund. The CEO, Michael Schade, described the decision to let Schmidt go as “painful” but in the interest of the club’s “further development and success”. The sporting director, Rudi Völler, underlined what the club has come to feel is the urgency of the situation.

“We have to act now if we do not want to completely lose sight of our goals,” Völler said. Immediately, that would probably be limited to preserving at least some form of participation in European competition next season. Leverkusen are five points off sixth-placed Eintracht Frankfurt. The top four, with Hoffenheim 11 points ahead, is surely already gone.

So is the Champions League for this season after that 4-2 first-leg defeat, even if the formality of a last-16, second leg at the Vicente Calderón is still to be fulfilled in nine days’ time. Schmidt’s players had run Diego Simeone and company close at the same stage two years ago. In fact, if they had erred in that tie, it was in only winning the home leg 1-0 and not capitalising on an excellent first-leg performance. Whether they aimed to be ultra-aggressive and avoid a repeat this time, or whether they had simply lost their discipline, they were cut open at will by visitors with issues of their own.

It felt as if Leverkusen were going backwards – and the faces of those players at the end of the match said as much. The wan performance in a home defeat by Mainz four days later, followed by Saturday’s flaming at Westfalen, did not alter the course of Schmidt’s fate but it quickened the end.

Expectation has played its part. Eight wins in nine at the end of last season meant nobody really classified Leverkusen as a dark horse coming into this campaign. In fact, with Dortmund bedding in a number of new players, many thought Schmidt’s ostensibly stable, well-drilled side could split Thomas Tuchel’s side and Bayern – or even put Carlo Ancelotti’s team under pressure.

Schmidt, in keeping with his upbeat brand of football, was optimistic to the end. “It sounds funny,” he reflected afterwards in the press conference room at Signal Iduna Park, “but it was a step in the right direction. I can live with this game much better than last week.”

The goalkeeper Bernd Leno, marking the occasion of his 25th birthday (‘celebrating’ might be a bit cavalier in the circumstances), would probably struggle to concur. Even if the Leverkusen tail wagged gamely, it could have been worse. Leno was called upon to make saves and Pierre-Emerick Aubameyang, who scored twice, also took an air shot with the goal at his mercy.

“We need team unity, tactical discipline and a lot of running,” Schmidt had said before the game. Meat Loaf might not so readily have accepted two out of three if the odd one out allowed his team to be pulled apart at will, by opponents simply refusing to look a gift horse in the mouth.

This was almost a carbon copy of the loss to Atlético, playing guilelessly into the hands of opponents with pace and firepower. Schmidt’s side have been making the same mistakes again and again; conceding, for example, a Bundesliga-high 16 goals from set pieces, the sort of stat that in recent seasons has been associated with no-hopers such as Stuttgart or Hamburg.

Leaving Karim Bellarabi and Chicharito on the bench here felt like a final throw of the dice – and not one that ever seemed especially likely to have the desired effect. Bellarabi, who scored the fastest goal in Bundesliga history in this fixture back in August 2014 – nine seconds into Schmidt’s league debut as coach – was summoned to try to put things right, replacing the floundering Charles Aránguiz after only 38 minutes, when Die Werkself were already two down. It was already too late.

Bernd Leno looks on after André Schürrle scored Dortmund’s fifth. Photograph: Lars Baron/Getty Images

The afternoon was Leverkusen’s season in a nutshell, featuring flickers of promise and no little effort on the path to ultimate disappointment. If we are being less charitable, the whole Schmidt ride has been a rollercoaster of soaring peaks and alarming troughs. The beauty of when it all clicks, which led to him being linked with the Bayern and Arsenal jobs down the line, glossed over the stumbles.

Last term, it was a poor restart post-Christmas that was the major wobble before they locked into gear. Even in his debut season, when Schmidt’s gung-ho credo was still a novelty, a damaging dip between mid-December and February put a question mark over him.

These dips had become the norm. The familiar, exhilarating pressing had become a scrappy parody of itself. When Tuchel complained about Leverkusen’s systematic fouling when they beat Dortmund 2-0 at the BayArena in October, it seemed like sour grapes. Here, it seemed like a loss of control. The referee, Christian Dingert, let a lot go, and incensed the Dortmund bench and players when he inexplicably failed to issue the already booked Bellarabi with a second yellow for a rough challenge through the elusive Ousmane Dembélé.

Regardless, Dembélé, Christian Pulisic and company put Schmidt out of his misery shortly after. His successor will be charged with bringing fresh identity to a highly talented squad and he will have to do it quickly, with Ömer Toprak already off to Dortmund in the summer and others unsettled. For the future, as well as the present, Leverkusen could not wait any longer.

Update: Tayfun Korkut has taken over as Schmidt’s successor until the end of the season. “With Tayfun Korkut, we have a trainer who has a great deal of expertise, who has a lot of experience both as a coach and a player on the international stage,” said Bayer’s Michael Schade on Monday lunchtime.

Talking points

• Bayern Munich’s 3-0 win at Köln wasn’t quite as comprehensive as it sounds – Manuel Neuer made one otherworldly save from Yuya Osako when the game was still goalless – but was still impressive. They negotiated a tricky start (against opponents who had not lost at home in almost 11 months) to slip into their irresistible best for just as long as was necessary, and Thiago Alcântara was imperious enough in the middle of the park to give Arsène Wenger nightmare flashbacks before Tuesday’s Champions League return at the Emirates. “Our play is more natural at this moment, said Ancelotti after the game. We have confidence.”

• On the other side of the Leverkusen collapse, Dortmund looked spritely before their more taxing European challenge, trying to turn around the perplexing first-leg defeat at Benfica. Aubameyang’s double confirmed his resurgent form – he looks a completely different player to the pale imitator of his best self that misfired in Lisbon – and it also allowed him to surpass Robert Lewandowski’s Bundesliga and overall goal totals for the club, which now stand at 75 and 105 respectively. The one disappointment was a thigh injury to Marco Reus that will keep him out until March, at the end of a week in which his good friend Mario Götze was ruled out indefinitely with a metabolic condition.

• Schalke were all at sea in the first part of their trilogy with Mönchengladbach. Saturday’s match, played in torrential rain, was the first of three meetings between the pair in 13 days, with the Europa League last-16 first leg in Gelsenkirchen on Thursday. The under-pressure coach, Markus Weinzierl, will thank goodness for home comforts anyway. Gladbach do not have many visitors who they enjoy seeing quite as much as Die Könisgblauen, having now beaten them on eight of their last nine visits. Dieter Hecking’s side look like they could win anywhere at the moment, though, and have taken more points than any other team post Christmas break. Fabian Johnson was the only change Hecking made to an XI who won the Pokal quarter-final at Hamburg but, in keeping with how swimmingly it’s been going for the new coach, it was a decisive one – he scored twice on the way to a 4-2 win that, in truth, probably even flattered Weinzierl’s team.

Fabian Johnson celebrates scoring against Schalke. Photograph: Ina Fassbender/AP

• Torsten Frings was determined not to get swept away in the romance of his return to Werder Bremen, with his Darmstadt team desperate for points. “Football is not fair,” the former Germany midfielder shrugged, matter-of-factly, after his side’s good start to this relegation scrap went unrewarded, notably with one stunning stop by the erratic Felix Wiedwald from Aytac Sulu before they succumbed 2-0. It has not been that easy on his former colleague Alexander Nouri either, with his team picking up more injuries here, including Clemens Fritz (again) and Zlatko Junuzovic. At least a third Bundesliga win in a row, inspired by Max Kruse’s double, will take some of the edge off as the tension eases.

• Andries Jonker, Wolfsburg’s third coach of the season, made his debut on the bench at Mainz. It was a competent enough display, although his side frittered away a lead given to them by Mario Gómez by conceding a shambolic equaliser shortly afterwards to Jhon Córdoba. “I’d have traded my goal for the three points,” Gómez told ZDF afterwards. Hamburg’s win over Hertha on Sunday means Die Wölfe are only above the relegation play-off spot on goal difference.

Results Frankfurt 1-2 Freiburg, Hamburg 1-0 Hertha Berlin, Köln 0-3 Bayern Munich, Mainz 1-1 Wolfsburg, Dortmund 6-2 Leverkusen, Mönchengladbach 4-2 Schalke, Hoffenheim 5-2 Ingolstadt, Bremen 2-0 Darmstadt, Augsburg 2-2 RB Leipzig.