1 Is fouling ever to be encouraged?
In the first leg Real committed only one foul on Robert Lewandowski, scorer of Borussia's four goals. In the build-up to the return José Mourinho, forgetting about Sergio Ramos's 10th-minute infringement, identified this as a problem: "We are so pure and so naive … How can you play 90 minutes and not commit a foul on a player who scored four goals?" The Pole was duly roughed up here, with Sergio Ramos marking him with questionable physicality, though the statistics will tell only part of the story. Only twice were Real actually penalised for fouling him (see No2), though Fábio Coentrão could have been sent off when he landed his studs on the forward's foot in the first half. Mourinho's motivational mastery is already legendary but this seemed a strange one.
2 Does Howard Webb freeze on the big stage?
Clearly Howard Webb is an excellent referee, widely respected by fans, players, managers and, obviously, assessors. His has been a glittering career, including the very biggest games in Britain and across the world, but he will be forever remembered for a key mistake: failing to send off Nigel de Jong for slamming his studs into Xabi Alonso's chest in the early stages of the 2010 World Cup final. There was a point last night – early in the second half when the 41-year-old interpreted Sergio Ramos's Hong Kong Phooey-style attack on the victimised Robert Lewandowski as a foul on the Spaniard – when memories of that moment returned. As in Johannesburg, one side last night seemed too often to get away with a deliberately physical approach.
3 Would Borussia be beguiled by the Bernabéu?
The stadium is the site of many famous comebacks and the Real defender Pepe claimed pre-match: "If there is a magic stadium in Europe, then it is the Bernabéu." But surely Borussia, with their three-goal cushion and memories of drawing 2-2 here, having led twice, in the group stages, would be immune? Apparently not: the visitors' display as the match got under way was error-strewn, leading to a series of chances for the home side and a string of inexplicably misplaced passes. Real's manic work rate helped to unnerve them and could not be sustained but, as the game continued, Dortmund wasted chances to end the contest with poor final passes or bad finishing, over-committed in attack towards the end and very nearly paid for it. Perhaps there is something in the magic, after all.
4 Giving the phrase 'reverse fixture' a new meaning
Until those breathless final few minutes, this match was everything that the first was not. Given that the first leg was packed with excellent attacking and blessed with immaculate finishing, this was not a good thing. Lewandowski would certainly have been the subject of many fewer salacious transfer stories over the last week had he been this profligate in the previous match. Ozil was perhaps the most impressive attacking force, yet he also missed probably the game's best chance (though Ilkay Gundogan later came close to matching it). The first match left home fans with mouths agape; in the second they were, for long periods, struck dumb. The game was defined by those early missed chances – all the last moments proved was quite how different the night could have been.
5 Do adverts get in the way of big sporting occasions?
Those watching on television in the UK witnessed ITV's greatest sporting howler since they accidentally screened an advert while England scored against USA at the 2010 World Cup. Gabriel Clarke, interviewing Mourinho in the tunnel post-match, dealt swiftly with the game (the Portuguese had the temerity to complain about Webb failing to send off a Borussia player). Then he turned to the coach's future. Would he be at Real next season? "Perhaps not." So where, then? "I want to be, I love to be where people love me to be." He seemed desperate to say more, but that's where Clarke's guillotine fell. "We'll take that as England," he said, butting in, as the credits rolled. Coincidentally, as in the 2010 incident, baffled viewers were left cursing an ad for the same company, Hyundai.