Arsenal 4-1 Galatasaray

• Welbeck scores first senior hat-trick
• Win on Wenger's 18th anniversary as boss
• Sanchez scores his fifth Arsenal goal
• Szczesny sent off for foul on Yilmaz

Danny Welbeck scored his first professional hat-trick as 10-man Arsenal swept aside Galatasaray in the Champions League.

Alexis Sanchez then curled home before Welbeck clipped in his third.

Burak Yilmaz scored a penalty after Arsenal goalkeeper Wojciech Szczesny was sent off for a foul, but it was nothing more than a consolation.

The win was Arsenal's first in this year's Champions League and means they have three points from two Group D games.

It was also the perfect way for manager Arsene Wenger to mark 18 years to the day since he was appointed Arsenal boss, and the Frenchman certainly deserves credit for naming an attack-minded side.

With Welbeck playing in his favoured central role and the former Manchester United striker ably supported by the pace and creativity of Sanchez, Mesut Ozil and Alex Oxlade-Chamberlain, the Gunners simply had too much for a Galatasaray side who have now failed to win in 10 visits to English sides.

Despite having lost their three previous away games in the Champions League, Galatasaray boss Cesare Prandelli started with a three-man defence, and it quickly became clear they were far too exposed at the back.

Just as they had in the 1-1 draw against Tottenham on Saturday, Arsenal dominated possession but the key difference in this game was they posed a greater threat going forward.

They pulled apart the Galatasaray defence for the opener as Sanchez raced on to Kieran Gibbs's pass down the left, cut inside and slid a clever ball for Welbeck, who got around Felipe Melo before poking a shot through the legs of Fernando Muslera.

Galatasaray rarely ventured forward as they tried to contain the Arsenal front four, and their nervousness perhaps contributed to a poor defensive error that allowed Arsenal to score a second.

Defender Aurelien Chedjou inexplicably headed straight to Welbeck midway inside the Galatasaray half and the striker showed good strength and composure to shrug off Melo before coolly beating Muslera.

That goal prompted flares to be lit in the away end, with some finding their way onto one corner of the pitch and causing a brief stoppage in play as they were put out.

Once the action resumed, so did Arsenal's dominance and Sanchez effectively put the game beyond Galatasaray when he ran through the defence to chase Ozil's ball before curling home from 15 yards.

The half-time whistle provided some welcome respite for Galatasaray, and Prandelli tried to stem the tide by introducing midfielder Hamit Altintop for the second half and reverting to a four-man defence.

Before the change could have the desired impact, though, Arsenal increased their lead further as Welbeck, brimming with confidence after his first-half double, grabbed his third of the game, timing his run for Oxlade-Chamberlain's pass to perfection before lifting the ball over Muslera.

It was no less than Welbeck and Arsenal deserved for a clinical attacking display that will give Wenger confidence that his side can progress from the group stage for the 17th successive season.

Szczesny took some of the shine off the victory when he was sent off on the hour. Yilmaz picked himself up to send substitute keeper David Ospina the wrong way from the spot, but by then the damage was done.