Cristiano Ronaldo scored his second Champions League hat trick to lead Real Madrid over Galatasaray 6-1 Tuesday night, and Manchester United, Manchester City and title holder Bayern Munich all opened with victories.
Ronaldo scored in the 63rd and 66th minutes of the Group B game, then added a goal in stoppage time in Istanbul. It was the 22nd club hat trick for Ronaldo, his first in Europe's top club competition since Oct. 3 last year at Ajax.
''Things could not have started better for us in this season's Champions League,'' Ronaldo said. ''Scoring six goals is really good, it will give us a lot of confidence.''
Karim Benzema had two goals and Francisco ''Isco'' Alarcon one for Real, which gave new signing Gareth Bale a start.
Madrid goalkeeper Iker Castillas started a competitive match for the club he captains for the first time since Jan. 23, when he broke a bone in his left hand. Relegated to the bench last spring by coach Jose Mourinho and earlier this season by new coach Carlo Ancelotti, Casillas was replaced by Diego Lopez in the 14th minute, three minutes after he injured his ribcage area in a collision with defender Sergio Ramos.
''Casillas has had bad luck and I hope he will be recovered in three or four days,'' said Ancelotti, without giving details of the injury.
Wayne Rooney scored twice to reach the 200-goal mark for Manchester United in a 4-2 win over Bayer Leverkusen, the three-time champions' first match in the competition since David Moyes replaced Alex Ferguson as manager. Robin van Persie also scored for the Red Devils in the Group A match, and Simon Rolfes and Omer Toprak had goals for the visitors.
Rooney played with his head bandaged because of a gash sustained during a collision with teammate Phil Jones during training on Aug. 31. Only Bobby Charlton (249), Denis Law (237) and Jack Rowley (211) are ahead of Rooney on United's career scoring list.
''I've concentrated on working hard to get my head down, to get myself fit and ready for the season,'' Rooney said. ''I'm delighted with the way I've come back and delighted I'm back playing and scoring goals. It's great the reception I get here and hopefully I can repay (the fans) with performances and goals like tonight.''
City won 3-0 at the Czech Republic's Viktoria Plzen in Group D on goals by Edin Dzeko, Yaya Toure and Sergio Aguero early in the second half. In the group's other game, Bayern beat visiting CSKA Moscow 3-0.
''We played well, especially in the first half,'' said Guardiola, who won the competition twice with Barcelona before replacing Josef Heynckes at Bayern lasty summer. ''I'm very proud. The first game back after winning the Champions League is never easy.''
David Alaba, Mario Mandzukic and Arjen Robben scored for Bayern, which beat Bundesliga rival Borussia Dortmund in the Champions League final last May.
''I could hear from fans today, 'Finale, Finale,' but let's keep our feet on the ground. We need to go step by step,'' Robben said. ''It's early in the season. The most important thing is to concentrate on ourselves, improve as we go on.''
Juventus rallied on Fabio Quagliarella's 54th-minute goal for a 1-1 tie at Copenhagen, which got a 14th-minute goal from Nicolai Jorgensen in the Group B match.
Shakhtar Donetsk won 2-0 at Real Sociedad in Group A on a pair of second-half goals by Alex Teixeira.
In Group C, Paris Saint-Germain routed Olympiakos 4-1 behind two goals from Thiago Motta and one each from Edinson Cavani and Marquinhos.
Vladimir Weiss had tied the score in the 25th minute for the hosts. Benfica beat visiting Anderlecht 2-0 as Filip Djuricic and Luisao scored. American midfielder Sacha Kljestan played the entire match for the visitors and was given a yellow card in the 76th minute.