dpaReal Madrid were tested away to Celtic on Wednesday but still began their Champions League title defence with a 3-0 win in Glasgow while Manchester City crushed Sevilla 4-0.Celtic started brightly but two clinical second half goals by Vinicius Junior and Luka Modric - delightfully with the outside of his foot - in the space of a few minutes gave Madrid control by the hour.The home side paid the price for missed chances and will rue captain Callum McGregor striking the post late in the goalless first period.Eden Hazard - who replaced the injured Karim Benzema - added a late third for Real.There was a shock in the other Group F game as Shakhtar Donetsk won 4-1 at struggling RB Leipzig, who were booed off to heap pressure on coach Domenico Tedesco.While Real are the record 14-time European champions, City are still chasing their first continental crown but again impressed to start Group G.Erling Haaland’s double eased them to victory ahead of their match next week against Borussia Dortmund, who started 3-0 at home to Copenhagen."I’m happy first of that we’ve won this must-win game,” Dortmund captain Marco Reus told Amazon Prime Video after opening the scoring."But we also know that we’ll have to improve next week against City because that’s a different quality on the pitch.” Raphael Guerreiro and Jude Bellingham were also on the scoresheet.Phil Foden scored between Haaland’s brace for City and Rúben Dias tapped in the fourth to heap misery on Sevilla who have made a poor start to the season.Paris Saint-Germain are also dreaming of a first Champions League title and began Group H with a 2-1 win over Juventus.Kylian Mbappe struck a double - the first a volley from a delightful Neymar scoop - to earn the points despite Weston McKennie cutting the deficit after the interval.Benfica defeated Maccabi Haifa 2-0 in the other tie.Chelsea, the 2021 champions, were stunned 1-0 at Dinamo Zagreb in Group E as Mislav Orsic raced clear to score the only goal in just 13 minutes.Debutant Pierre-Emerick Aubameyang had a potential equalizer disallowed for offside and Reece James smacked the post "It’s an underperformance from us,” Chelsea manager Thomas Tuchel told BT Sport. "We have the same story as always. We have an OK start, we don’t finish our half chances, we don’t feel it when the game is already there to put to bed in the first 15/20 minutes.Red Bull Salzburg drew 1-1 with AC Milan in the other match.Wednesday’s games include Napoli v Liverpool in Group A and Inter Milan v Bayern Munich in Group C.