( CNN ) -- Cristiano Ronaldo underlined just why Real Madrid agreed to pay him the big bucks on a scintillating evening of European football . The 28-year-old , who inked a new five-year deal with the Spanish club on Sunday , completed a brilliant hat trick as Real raced to a 6-1 rout against Galatasaray . Ronaldo had the final say in Istanbul as he danced past three defenders before blasting the ball into the net for his hat-trick . Summer signing Isco had got Los Blancos off the mark when he picked up a long ball hit from beyond the halfway line by Angel di Maria and hit home after 33 minutes . From then on it was one way traffic as Karim Benzema and Ronaldo added two goals apiece before Umut Bulut pulled one back for the Turkish champions . The away victory saw the nine time European champions kick off a new era of European football under manager Carlo Ancelotti in some style . A pulsating opening round of Champions League group matches featured a flurry of firsts . Former Barcelona boss Pep Guardiola safely negotiated his first match in charge of Bayern Munich 's title defence with an emphatic 3-0 win over CSKA Moscow . David Alaba hit home a dipping free kick to set the Germans on their way before Mario Mandzukic powered in a header in a dominant first half . Arjen Robben volleyed in a scooped pass from Alaba to tick off a first European win for Guardiola and his defending champions . David Moyes also came through his first game as Manchester United manager unscathed as the club made its first European outing without Sir Alex Ferguson at the helm since 1985 . Wayne Rooney -- wearing a thick headband to protect an injury - set United on their way as he bundled home Patrice Evra 's cross after 22 minutes . Bayer Leverkusen leveled the match at Old Trafford in the second half thanks to Simon Rolfes . But the German side 's relief was short lived as , just five minutes later , Robin van Persie scissor kicked the ball into the net to put United back in front . Moyes watched Rooney -- the star striker he sold to United from Everton in 2004 -- pounce again with his 200th goal for Manchester United . The 27 year old coolly slotted in a low drive to become only the fourth player in the club 's history to reach the landmark . United poured forward on the break with some brilliant flowing play that was finished off with a fourth goal from Antonio Valencia . With two minutes on the clock , Omer Toprak pulled back another away goal for Leverkusen but United came off the pitch 4-2 winners in the Group A clash . In the Czech Republic , Manchester City recovered from a tentative start to cruise to a 3-0 away win against FC Viktoria Plzen . New City boss Manuel Pellegrini led Malaga to the Champions League quarter finals last season and was looking for a positive display from his new charges . Edin Dzeko broke the deadlock after half time when he slotted home a pass from Sergio Aguero , who used his muscle to hold off the Czech defence . Yolo Toure conjured a curling goal from nowhere to double City 's advantage before Aguero finally got on the score sheet to complete a pleasing away win . Paris St Germain also earned a 4-1 win away at Olympiakos while Italians Juventus were held to a 1-1 draw by FC Copenhagen .
Cristiano Ronaldo sinks a hat trick as Real Madrid beat Galatasaray 6-1 . Bayern Munich grabs his 200th goal for Manchester United as they beat Bayer Leverkusen 4 -2 . Defending Germans champions Cristiano Ronaldo see off CSKA Moscow 4 -0 . Czech Republic defeat Viktoria Plzen in Czech Republic .