The Polish champion was ordered by UEFA to play its home match against the Spanish giant behind closed doors, after crowd trouble marred the opening day 6-0 defeat against Borussia Dortmund.
Crowd disturbances, fireworks, throwing objects, insufficient organization and blocking stairways forced Europe's governing body to implement a total stadium ban for home fans and an €80,000 ($88,820) fine.
A further charge of racist behaviour was dropped.
There were still a number of Real fans present in the Polish Army Stadium, albeit very few, as the away side and the Spanish FA were allowed to register up to 200 people as visitors.
"There is no advantage," coach Zinedine Zidane said Tuesday of playing in front an empty stadium. "I always prefer to play in front of supporters even away from home, because that's what football is all about."
And over the course of the 90 minutes, it certainly seemed as though his players failed to adapt to this unusual setting.
However, few still expected anything other than a Real victory and the visitor took the lead after just 57 seconds -- its fastest ever Champions League goal -- thanks to Gareth Bale's stunning volley.
Not a bad way to celebrate a new contract.
Things continued to follow script as Karim Benzema doubled Real's lead, stylishly finishing of a wonderful, flowing team move.
However, despite the lack of home support from the crowd, Legia started its fightback, as Vadis Odjidja-Ofoe curled a wonderful strike into the top corner to leave Real 10 games without a clean sheet.
Legia's form both domestically and in Europe this season has been fair from inspiring.
The reigning Polish champion had lost all three of its Champions League games, while languishing in sixth in the Polish first division, 10 points off top spot.
Nothing suggested Odjidja-Ofoe's strike was anything more than a flash in the pan but less than 15 minutes into the second half, Legia found an equalizer.
A long-range toe poke from Miroslav Radovic skidded under the hands of Keylor Navas to send those on the Polish bench into raptures.
Then the unthinkable happened.
With Zidane opting for a 4-2-4 formation in an attempt to shoehorn his attacking quartet of Cristiano Ronaldo, Bale, Benzema and Alvaro Morata into the side, Real's defense was left exposed time and again.
Indeed, it was another counter-attack which proved to be its undoing, as Thibault Moulin curled a shot off the inside of Navas' post to give the Poles an inconceivable lead.
With just seven minutes to hold on, Legia could start to dream of recording one of the most famous wins in the club's history.
But just two minutes later, Mateo Kovacic brought them crashing back down to earth as the Croat threaded a shot through several Legia bodies and into the bottom corner.
Ronaldo cut a subdued and frustrated figure all evening and was unable to inspire a Real comeback, leaving the Portuguese on 98 Champions League goals.
Legia will undoubtedly leave delighted with a first point of the campaign -- although what could have been -- but what a pity there weren't any fans to witness a classic European tie.
In Group F's other fixture, Borussia Dortmund took full advantage of Real's slip-up with a hard-fought 1-0 win at home to Sporting.
Victory ensures the Germans are the only side to qualify for the last 16 Wednesday, going two points clear of Real and seven clear of Sporting with just two games left to play.