Karim Adeyemi scores hat-trick as Borussia Dortmund beat Celtic | Champions League

The Champions League has a habit of inflicting these inglorious episodes on Celtic. It's hard to escape the idea that this large fish will always drown if removed from its small home pond. Borussia Dortmund played with their guests in a game that ended as a fight long before the half-time whistle. The Germans won two out of two games in this new format. They have the ambition to build on last season's memorable tournament run, even if far tougher tests lie ahead. It was like a grandmaster watching an orangutan play chess. Men against Bhoys.

Suddenly there is pressure on Celtic's upcoming trip to Atalanta. The poor performance they showed here undermined the oft-quoted opinion that Celtic were better equipped for the Champions League than at any time in recent history. It was a fragile representation riddled with errors. Brendan Rodgers has now managed three different Celtic teams who have conceded seven goals in a single Champions League game. There is also a six and a five in the Rodgers record.

“It was a tough time,” admitted Rodgers. “Nights like that are tough, but at this level it can happen. You have to learn from it and move on. Our confidence was high, but we had to start the game much better than we did.”

The European football association had already made a profit before a ball was kicked. A fine will inevitably be handed out after the teams appeared in front of huge banners on the Yellow Wall branding UEFA a “mafia”. The slogan underneath read: “You don't care about sport, all you care about is money.” Pyrotechnics from the Celtic support will also trigger a sanction.

A crazy opening soon diverted attention from what was happening in the stands. Celtic did exactly what they were desperate to avoid by giving Dortmund the momentum, but then fought their way back into the game and conceded a second goal that was as defensively poor as the hosts' first.

It was a touch of luck that Jamie Gittens won a penalty against a desperate Kasper Schmeichel. Gittens won Celtic captain Callum McGregor's attack on the ball as he broke out of midfield. Nevertheless, the Dortmund player should have been stopped long before Schmeichel had to knock him over. Emre Can's reunion with Rodgers, once his manager at Liverpool, was positive for the midfielder as he sent Schmeichel the wrong way from 12 yards.

Celtic responded immediately. A wonderful cross from Arne Engels from the right left the Dortmund defense on the wrong foot. Daizen Maeda sneaked in, scored – via the belly – and caused wild scenes among the guests.

This joy was short-lived. The third goal in four minutes was scored by Karim Adeyemi, who outpaced Auston Trusty before firing a shot past Schmeichel using a deflection from the same defender. In the first half, Dortmund kept thwarting Celtic with astonishing ease. In view of the Scottish champions against the elite of Europe, it sounded incredibly familiar to me.

Adeyemi, who played a central role in everything good about Dortmund, scored his team's third goal. At this point Celtic were in a bind. Again there was generosity involved; the kind that usually goes unpunished in Scotland. Celtic only half cleared a corner, Adeyemi grabbed the loose ball. Schmeichel obviously wasn't expecting a shot that flew past him from a tight angle at the near post.

Celtic had conceded four goals all season before this game. Another penalty gave the same score within 40 minutes. Engels carelessly kicked Adeyemi in the foot, leaving the referee no choice but to intervene. Adeyemi mercifully passed up the chance of a hat-trick – he would have expected it anyway – and this time Serhou Guirassy did what was necessary.

It was five o'clock at break time. Adeyemi actually got the treble his outstanding performance deserved with a low shot after Maeda won possession. Dortmund had been ruthless. Celtic's goal difference in their 5-1 win over Slovan Bratislava was equalized in a dizzying half. Rodgers believed his players were “spooked” in that opening period.

The heartbroken Adeyemi limped off the pitch three minutes after the restart. This was the biggest boost to Celtic's night. Schmeichel redirected Julien Duranville's shot around the post as Dortmund chased down their half-dozen. However, the intensity of Nuri Sahin's team decreased significantly. Her job was essentially done.

Number six actually came. Alistair Johnston passed the ball straight to the opposition, which resulted in Guirassy taking on Liam Scales. The Celtic centre-back was confidently beaten before Guirassy wrong-footed Schmeichel. Another comedic defense brought Dortmund seventh place. Trusty, who was going through a difficult time, gave the ball away. Felix Nmecha returned it with interest. Celtic's latest horror show ends here.