Celtic left with mountain to climb after André Silva’s rapid double for Leipzig

The pride and optimism that filled Celtic before their Champions League campaign this season is quickly giving way to a harsher, colder reality.

Defeat here leaves them with one point from three games, and means they will probably have to get something away at Real Madrid to qualify from Group F. Which is not impossible, of course. But with every step they are learning some stern lessons and this time it was the turn of a skittish but improving Leipzig side to dish them out.

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It could have been a proper thrashing. Leipzig had two goals disallowed, created numerous overlaps and openings, ran through a flimsy Celtic defence that was in turn severely exposed by its midfield and let down by its goalkeeper, Joe Hart. Afterwards, Ange Postecoglou pointed to the number of chances Celtic created, as well his side’s inexperience at this level. But he will also know deep down that Celtic are much further from the European elite than many of their fans like to imagine.

André Silva got the two decisive goals in a merciless 13-minute burst that left Celtic gasping for air. In reality, the game could well have been safe before or after that. It was a wild, bruising, and richly entertaining encounter, with a looseness that at times bordered on chaos and a frenetic pace punctuated only by the numerous injury-enforced breaks in play.

The Leipzig goalkeeper, Peter Gulacsi, went down within the first 10 minutes and the Celtic captain, Callum McGregor, had followed him before half-time. Certainly the openness seemed to suit the home side better than Celtic, who for all their energy and enterprise, looked porous and fragile every time Leipzig poured forward on the break. Naturally a good deal of the criticism will fall on their makeshift centre-back pairing of Moritz Jenz and Stephen Welsh and the calm assurance of Cameron Carter‑Vickers was badly missed.

But really the failure was collective, a team that had neither the technical quality to control the game, nor the positional discipline to close it down, nor the required cutting edge up front. These are flaws that are forgiven at domestic level. But not here.

For Leipzig further evidence of their progress under their new manager, Marco Rose, who has been in the job for a month since the sacking of Domenico Tedesco. While Silva will grab the plaudits, it was Christopher Nkunku who was the game’s decisive presence, putting Leipzig ahead on 27 minutes after a lightning counterattack, and spending the rest of the tie on some elevated plane of existence: impregnable and untouchable.

There was a certain valedictory yearning to the way the Leipzig fans sang his name, in the knowledge that a move to Chelsea is imminent: part sadness and part gratitude, a recognition that few players have played a bigger part in the club’s rise.

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Celtic, depleted by the loss of their captain, continued to plug away. Two minutes into the second half they were rewarded for their persistence: Reo Hatate winning the ball high, Kyogo Furuhashi squaring for Jota, a calm low finish. Here, perhaps, came the crossroads of the match: caught between attack and defence, aggression and caution, Celtic ultimately opted for neither. “We got a bit negative in our mindset, invited pressure,” Postecoglou said. “We kept going back to Joe for no reason. You can’t play to survive at this level.”

Will Hart survive at this level? Everyone knows his strengths and weaknesses by now and perhaps it was only a matter of time before his footwork was exposed. Just seconds after Dominik Szoboszlai had a goal disallowed because Silva was obscuring Hart’s vision while standing in an offside position, Hart received the ball and promptly passed it straight to Szoboszlai, who played in Silva for an easy finish. “I wasn’t quite sure whether to go to the centre-half or Greg [Taylor],” Hart said afterwards. “I decided to go for Greg. And I missed.”

Not long after that Silva made the game safe. Once more Leipzig killed Celtic with a diagonal ball, once more Mohamed Simakan surged forward from right-back, once more Jota failed to keep pace with him. Simakan’s first-time cross found Silva, who had time to take a touch before tucking the ball in. In many ways it was a goal that summed up Celtic’s campaign so far: one in which, for all their good intentions, they have found themselves badly off the pace.