A riveting first-half preceded a reticent second-half as Manchester United held Real Madrid to a 1-1 scoreline with a stout European away performance.
Here are five things learned from the round-of-16's glamour tie...
ROONEY THE EUROPEAN EXPENDABLE
When Cristiano Ronaldo was at Manchester United Wayne Rooney's name was still inked on the teamsheet ahead of the Portuguese. A flexible forward who became the sacrificial lamb in European matches, Rooney accommodated Ronaldo's maturity to Champions League-winning effect in 2008 and to another final the following year. However the arrivals of Shinji Kagawa and Robin van Persie now put his place at jeopardy in these games, and he picked the worst possible time to give one of his worst performances in a red shirt.
Most acknowledge Rooney won't emerge into the player those at Everton hoped and expected a decade ago but his footballing brain is still as sharp as a pin. But in the Bernabéu it was blunt. Returning to a stadium which hosted one of his lowest ebbs with England in 2004, his inability to control or pass was worrying especially when his form has been good of late.
With United holding a slight advantage and the Old Trafford factor potentially decisive in the return leg, Sir Alex Ferguson will likely retain Rooney with the intention of playing more adventurously. However the self-proclaimed "big man" is in danger of becoming small.
MADRID MISSED PEPE PRESENCE
Ferguson could be forgiven for a critique of the referee after he neglected to book a single Real player and failed to sent off defender Raphaël Varane after he tripped up Patrice Evra. Varane, excellent against Barcelona in the Copa del Rey Clásico two weeks ago, looked daunted and unsettled by the speed of Danny Welbeck and the craft of Robin van Persie than the threat of Lionel Messi.
Pepe, not risked as he continues to recover from an ankle problem, nevertheless remains one of Mourinho's trusted troops who is as composed as he is cunning. Sergio Ramos took over the latter skill with some feigned agony to get Van Persie and Valencia booked but he looked bereft without his preferred partner whenever United ventured into Madrid's third.
Varane, although an excellent back up, should probably be sat on the bench in three weeks' time. He'd be lucky to have that privilege thanks to the myopic referee.
UNITED ESCAPE DESPITE POOR POSSESSION PLAY
Ferguson hasn't signed a central midfielder since 2007 and although he can get away with such negligence in the regressive Premier League, the Champions League offers what he called an "acid test" and to an extent, his midfield didn't pass it.
With ball retention and pressing an increasingly indispensable quality in European football, United failed on both counts again as they revisited the long ball tactics of the 2009 Rome final. In Madrid they relied on the bulldog spirit of Michael Carrick and, in particular, Phil Jones. The latter resembled an England international in one of those quarter-finals which ends in a glorious failure, only his intervention at the death prevented Ronaldo from scoring what would almost certainly have been the winner.
"The disappointment for me was that we sat back too often," Ferguson reflected on the period after United took the lead. What they lacked in imagination they made up for with industry.
HIGUAÍN MAY HAVE EARNED OLD TRAFFORD START
Karim Benzema is a better footballer and striker than Gonzalo Higuaín and the constant rotation of the duo may continue at Old Trafford. Benzema struggled against Rio Ferdinand and Jonny Evans as he became one-dimensional despite Ronaldo and Angel di María encouraging variety up front. Higuaín's adroit movement meanwhile almost culminated in a goal for Fabio Coentrão, as he worked United's defence more in half the time than Benzema had.
WELBECK JUSTIFIES INCLUSION
Selected due to his gamely work-rate and cover for Patrice Evra, it was ironic Danny Welbeck ended a drought of nearly four months to open the scoring. His movement to lose a two-time European Championship and World Cup winner in Ramos belied his lack of composure in the final third this season, but it was what followed afterwards which would have pleased the long-legged Longsight forward's manager.
With long balls into the channels tailored for Welbeck's pace, he rarely let his teammates down and on the rare occasion United had possession behind Xabi Alonso and Sami Khedira Madrid looked genuinely fearful when Welbeck bore down on them. Time will tell whether the match was a seminal moment for the 22-year-old, as he became only the fifth United player to score away at Real Madrid.