The defending champions got off to the best possible start earning three points on the road, but they did lose their star player due to injury.
An entertaining first half
Under cloudy and foggy conditions at Celtic Park, the defending champions began their title defense against the Scottish league champions.
The first serious scoring opportunity came in the 12th minute as Liel Abada was sprung in alone on Thibaut Courtois but was able to make the first save of the game.
The home side came pretty close to taking the lead in the 21st minute as Callum McGregor shot from in close rang off the post and stayed out.
Real Madrid took a massive hit in the 30th minute as Karim Benzema came out of the game as he seemed to have injured his knee and was replaced by Eden Hazard.
In the 43rd minute, Vinicius Junior had a wonderful chance as he went in alone on Joe Hart but Hart came out and make a spectacular save to keep the game scoreless
Vinicius had another chance two minutes later but his shot went right into the hands of Hart.
Real Madrid takes over
Real Madrid manager Carlo Ancelotti made a change to start the second half bringing in Toni Rudiger for Eder Militao. The visitors took the lead in the 55th minute as Federico Valverde found Vinicius who buried it past Hart.
Five minutes later Luka Modric doubled Madrid's lead as he got the ball and beat Hart with a powerful strike. Ancelotti made his third change of the game bringing in Eduardo Camavinga for Aurelien Tchouameni.
Eden Hazard made it 3-0 for Real Madrid in the 77th minute as he finished a play by getting a great pass from Dani Carvajal and putting the ball into the back of the net.
Ancelotti made two more changes three minutes later bringing in Marco Asensio and Rodrygo for Vinicius Junior and Luka Modric. After two minutes of added time, the final whistle blew and Real Madrid started their title defense with a big win on the road.
With the condensed group stage schedule, thanks in large part to the World Cup in November Real Madrid are scheduled to face RB Leipzig in their next match at home in Madrid at the Estadio Santiago Bernabeu.