Celtic seen off by Real Madrid who begin Champions League defence with win
The Scottish champions were left to rue not making the most of a bright start as Callum McGregor (29) rattled the post.
However, the Hoops had no response once Vinicius Junior, scorer of the winner in last season's final, broke the deadlock with a calm finish on 56 minutes.
Four minutes later a nonchalant finish from Luka Modric (36) with the outside of his foot doubled Madrid's lead before Eden Hazard (31) struck to continue a 100 percent start to the season for Carlo Ancelotti's men.
Celtic had begun the night with a perfect record this season, including a 4-0 demolition of local rivals and Europa League finalists Rangers on Saturday.
But in their first Champions League group match for five years, Ange Postecoglou's men were given a harsh lesson of the need to take their chances in the step up to the highest level in European football.
The return of the Champions League anthem was met by a guttural roar of 60,000 packed into Parkhead and the home fans nearly had a goal to celebrate inside the first minute when Liel Abada's strike was deflected just wide.
Postecoglou promised to stay true to his attacking philosophy against the European champions and stayed true to his word.
Abada should have done better when he shot tamely into the arms of Thibaut Courtois and McGregor's fierce effort came crashing back off the post as the hosts had the better of the opening 20 minutes.
Ancelotti started with 10 of the 11 that began last season's Champions League final success over Liverpool with 80-million-euro ($84 million) signing Aurelien Tchouameni replacing the departed Casemiro.
But Los Blancos were forced into a change after half an hour when Benzema hobbled off with a knee injury to be replaced by Hazard.
Madrid's superior quality still slowly began to show with Modric and Toni Kroos taking control of midfield as the ferocity of Celtic's pressing slowed.
Only a fine save from Joe Hart prevented Vinicius opening the scoring before the break after the Brazilian broke the offside trap to gallop clear in behind the Celtic defence.
Celtic had one more big chance to strike first blood when half-time substitute Daizen Maeda turned Josip Juranovic's cross weakly into the arms of Courtois.
Postecoglou wheeled away in frustration with the sense his side could ill afford to waste such opportunities and so it proved.
Vinicius was deadly when given a second chance up against Hart as he steered Federico Valverde's cross into the bottom corner.
Celtic were barely able to catch their breath before conceding again as Modric wriggled free inside the area and had just too much on his finish to beat Hart's right hand.
Hazard then grabbed his first goal since January to round off the scoring and a brilliant team move as the Belgian tapped home Dani Carvajal's pinpoint cross.
kca/mw