Three goals up, having limited Feyenoord to a handful of potshots, Manchester City could hardly have been more comfortable as Tuesday's game entered the final quarter of an hour.
After the run of five consecutive defeats which had thrown their season into turmoil, it seemed Pep Guardiola's side were taking an invaluable step to getting back on track, just in time for their Premier League showdown with leaders Liverpool on Super Sunday.
The Manchester City manager's confidence was such that he had just made a triple change, withdrawing Nathan Ake, Ilkay Gundogan and Phil Foden for some hard-earned rest and giving minutes to Kevin De Bruyne, James McAtee and Jahmai Simpson-Pusey.
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An uneventful conclusion beckoned.
Or at least that's how it felt.
Instead, a bewildering 15-minute collapse, the latest by any side with a three-goal lead in the history of the Champions League, a competition City won only last year, means they will head to Anfield on the back of their most painful result yet.
And that is saying something coming three days after the heaviest home loss of Guardiola's career against Tottenham.
Gvardiol gifts Feyenoord their first
It all changed in an instant.
And as against Spurs on Saturday, it started with a Josko Gvardiol error.
De Bruyne and Gvardiol look dejected
Image: De Bruyne and Gvardiol look dejected during the game
Simpson-Pusey's header, after Manuel Akanji had half cleared an attempted long pass, was awkward for the Croatia international, who had Feyenoord forwards applying pressure either side of him, but he still should have been able to deal with it.
Instead, his horribly-misjudged pass-back looped agonisingly into the path of Anis Hadj-Moussa, who got there well before the stranded Ederson, to touch the ball around the goalkeeper and slide home a smart finish from an acute angle.
Anis Hadj-Moussa slides the first goal into the net after beating Ederson
Image: Anis Hadj-Moussa slides the first goal into the net after beating Ederson
It was the latest in a series of costly defensive errors from Gvardiol, who was at fault for Spurs' second goal as well as their opener.
Soon, what looked at first like a consolation goal for the visitors came to mark the start of an epic collapse.
City switch off as deficit cut
Seven minutes later, the deficit was cut to one goal and the alarm bells were ringing loudly.
City had eight defenders either in or just outside their penalty area when Igor Paixao received Hwang In-Beom's pass near the right-hand corner of the box and yet both players found ample space.
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Erling Haaland and Pep Guardiola
Ben Ransom is joined by Adam Bate to analyse Manchester City's collapse against Feyenoord
McAtee was too late in getting the right side of the latter, while Bernardo Silva's attempt to stop the former's cross was half-hearted, giving him the freedom he needed to lift a diagonal delivery towards the far post, where City were disorganised.
Gvardiol had been late to spot Quinten Timber over his shoulder, while, on the outside, Matheus Nunes failed to track Jordan Lotomba altogether, allowing the right-back, who had come on as a substitute only 10 minutes earlier, to volley the ball towards goal from near the byline.
Santiago Gimenez had the simple task of chesting the ball over the line
Image: Santiago Gimenez had the simple task of chesting the ball over the line
Santiago Gimenez celebrates scoring Feyenoord's second goal
Image: Santiago Gimenez celebrates scoring Feyenoord's second goal
At his near post, Ederson seemed to be caught off-guard, sticking out a leg and sending the ball crashing off the upright and across goal, where a sleeping Akanji had left the unmarked Santiago Gimenez with the easy task of chesting the ball over the line.
Ederson errs again as Feyenoord level
City looked shell-shocked at this point.
Feyenoord, meanwhile, clearly sensed their opportunity.
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Manchester City's Josko Gvardiol reacts after Feyenoord's Santiago Gimenez scored a goal during the Champions League opening phase soccer match between Manchester City and Feyenoord at the Etihad Stadium in Manchester, England, Tuesday, Nov. 26, 2024.
Tim Sherwood couldn't believe the 'capitulation' of Manchester City against Feyenoord
Their third goal was probably the worst of the lot from a defensive perspective, coming as it did from a Hadj-Moussa ball over the top from an innocuous position, 10 yards inside his own half near the right-hand touchline.
In the penultimate minute of normal time, needing to simply play it safe and see out the closing stages, City were instead pushed up towards the halfway line. Their ragged defensive line was gleefully exploited.
Hadj-Moussa could have aimed his pass towards any one of four Feyenoord runners, but it was Paixao he found. Ederson came steaming out of his box in an attempt to clear the danger but got nowhere near it.
Ederson is beaten to the ball by Feyenoord's Igor Paixao in the build-up to the third goal
Image: Ederson is beaten to the ball by Feyenoord's Igor Paixao in the build-up to the third goal
The winger, like Hadj-Moussa before him, had numerous targets to aim for with his subsequent cross. Hwang, Gimenez and Timber were all racing into the box untracked, with City players far too slow to get back.
In the end, Paixao picked the onrushing left-back David Hancko, who had sprinted freely into the box from the opposite flank to meet his team-mate's cross with an easy headed finish, sparking jubilant Feyenoord celebrations and ensuring their stunned hosts hit a new low.
David Hancko heads the equaliser past Rico Lewis
Image: David Hancko heads the equaliser past Rico Lewis
Hancko had run untracked from inside the Feyenoord half
Image: Hancko had run untracked from inside the Feyenoord half
Hancko wheels away in celebration after his goal
Image: Hancko wheels away in celebration after his goal
Man City pushed back into the mire
Guardiola was at a loss to explain the collapse afterwards.
"The game was good for the confidence, we were playing at a good level, and then when the first thing happens, we have problems," he said.
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Manchester City's Bernardo Silva, second right, reacts after Feyenoord scored their third goal during the Champions League opening phase soccer match between Manchester City and Feyenoord at the Etihad Stadium in Manchester, England, Tuesday, Nov. 26, 2024.
Pep Guardiola says Manchester City's loss of a three-goal lead to Feyenoord to draw 3-3 in the Champions League was 'difficult to swallow'
He bemoaned a lack of focus. "It's not about not running or no commitment, but in football you have to be [switched on] in certain moments to do it."
City, once again, where found wanting in those moments and the errors continue to stack up.
Man City's defensive 'errors leading to goals' count on the rise
Image: Man City's defensive 'errors leading to goals' count on the rise
According to Opta, they have already made more mistakes leading to goals than in the whole of last season. They are more than halfway to matching last season's total for errors leading to shots.
They remain glaringly vulnerable to quick, direct attacks but Feyenoord's three goals all came in different circumstances, underlining the scale of City's problems right now.
Fail to stamp out the issues at Anfield on Sunday and this extraordinary run is likely to continue. This was a draw that felt like a loss and leaves their season at risk of imploding.
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