Good evening everyone. Every game in the Champions League is a big one, but this could be a particularly crucial night for Arsenal. They head into their second Group B fixture without a point as Galatasaray make the trip to the Emirates Stadium.

Arsene Wenger has been superb at getting his side into the knockout stages over the years, but the pressure is on the Gunners after just one game. They're currently bottom of Group B following a disappointing defeat to Borussia Dortmund a fortnight ago. Arsenal simply have to win their home games.

Galatasaray will not be easy opponents for the hosts tonight. They snatched a draw with Anderlecht in their first game, but certainly have the potential to cause the Arsenal defence problems. Cesare Prandelli has insisted that his side will be brave in North London tonight.

It's fair to say we haven't seen the best of Arsenal yet this season. Injuries have certainly contributed to that, but Wenger will know what an emphatic win could do for his players tonight as they look to hit top form. It could be a big night for the team.

ARSENAL: Szczesny, Chambers, Mertesacker, Koscielny, Gibbs, Flamini, Cazorla, Ozil, Alexis, Oxlade-Chamberlain, Welbeck

SUBSTITUTIONS: Ospina, Coquelin, Bellerin, Rosicky, Wilshere, Campbell, Podolski

The big news for Arsenal is that Jack Wilshere is on the bench for tonight's game. Arsenal were positive about his fitness after he picked up an ankle knock against Tottenham Hotspur, but Wenger has refused to risk the midfielder from the start. That means Alex Oxlade-Chamberlain could start in a central position, with Mathieu Flamini playing in a holding role. As you would probably expect, it's a very attacking lineup from the hosts.

GALATASARAY: Muslera, Chedjou, Melo, Semih, Veysel, Yekta, Dzemaili, Telles, Sneijder, Pandev, Yılmaz

SUBSTITUTES: Bolat, Çamdal, Hakan Balta, Altıntop, Bruma, Olcan, Umut Bulut

It's as expected from Prandelli, who looks to be sticking with a 3-5-2 formation for the game against the Gunners. In attack, it's Goran Pandev and Burak Yilmaz who lead the line for the visitors, with support arriving from Dutch playmaker Wesley Sneijder. Hamit Altintop is back on the bench.

Wenger is celebrating the 18th anniversary of his appointment as Arsenal manager this week. In the modern game it really is an incredible achievement to stay at a club for so long. After he leaves, will we ever see it happen in England again? He will be desperate to win the Champions League before he departs, though. Not many are expecting the Gunners to challenge for the trophy, but with their attacking talent, who knows what will happen?

You will remember that Arsenal have already faced Turkish opposition in this season's competition. The Gunners edged out Besiktas with a 1-0 triumph over two legs of the final qualifying round thanks to Alexis Sanchez's strike in North London.

0 - Excl. pen shootouts, Arsenal have never lost a game versus a Turkish opponent (W5 D4), keeping a clean sheet in 8 of these 9 games. Form — OptaJoe (@OptaJoe) October 1, 2014

There's plenty of other games you can enjoy with Sports Mole tonight as the Champions League continues. You can follow live text coverage of any fixture by clicking on the match in the box on the right of the page.

Supporters of these two sides will be eager to keep an eye on Anderlecht vs. Borussia Dortmund this evening. Arsenal, in particular, will know that their chances of finishing top will be slim if they drop points and Dortmund record another win.

KEY PLAYER: As we've mentioned, it's imperative that Arsenal collect all three points this evening. If they do, I believe that Oxlade-Chamberlain is going to play a big role. The midfielder showed signs of hitting his top form in Saturday's North London derby, and he'll relish being the main man in the middle of the pitch tonight.

© Getty Images

KEY PLAYER: It might seem like a very obvious choice, but Galatasaray need Sneijder to deliver tonight. When they signed the Dutchman, it's games like these they were expecting him to stand up and take on the responsibility of being the playmaker. Sneijder will be vital when the visitors are in possession, and he holds the key to bringing Pandev and Yilmaz into the game.

Prandelli believes that it will be crucial for his team to stick to their own game this evening. They may be underdogs, the Galatasaray boss certainly seemed optimistic in his pre-match press conference yesterday.

"We will make sure whenever we lose the ball, we will get it back quicker," the Italian told reporters. "We have to be brave, to be courageous and make sure we play our own style.

"For us, it is important to get out as a team, to defend strong. We must have respect, that is important, but not be afraid."

PREDICTION: Kickoff is just 15 minutes away, so it's time to look into Sports Mole's crystal ball, which is definitely not 100% accurate. It's a tough match to call tonight. Galatasaray are tough opponents for the Gunners, and have the ability to cause problems on the break. However, I'm going for a 2-1 Arsenal win.

Danny Welbeck has a big role to play for the home side tonight. He's blown hot and cold since arriving from Manchester United, but he needs to prove that he can lead the line for a Champions League side. It's a big night, and he has to respond with an impressive display.

.@19SCazorla and Tomas Rosicky soak up the Emirates Stadium atmosphere as they warm up before #AFCvGAL pic.twitter.com/OomS1ycEfP — Arsenal FC (@Arsenal) October 1, 2014

Galatasaray are notoriously poor travellers, and are looking for their first win in England in 10 attempts tonight. In the past they've been guilty of being far too generous at the back. Has Prandelli inserted some Italian discipline during his short stay at the club?

There's been plenty of talk about empty seats at English grounds this week, but there will surely be a full house at the Emirates Stadium tonight. The passionate Galatasaray supporters will make it an even better occasion. They're making themselves heard already. The teams are on their way out of the tunnel now.

Here we go then. Everyone seems to be ready for the start of this match. Galatasaray will get the game underway.

The noise coming from the visiting supporters is quite incredible. Not many sets of supporters who can claim to be louder. Decent start to the game from the away side.

Chamberlain looks to be starting the match on the right, with Ozil in his favoured position behind the striker. That leaves Cazorla and Flamini as the two central midfielders. The Spaniard will have to show a slightly different side to his game tonight.

Good work from Ozil as he forces his way into the box by exchanging passes with Welbeck, before seeing a powerful shot blocked inside a congested area. It's a very open game already.

Telles has shown his desire to get as far forward as possible early in the game, and the three central defenders certainly allow him to do that on the left. Chambers comes across well to clear the danger when he threatens to find space.

Good spell of pressure from the Gunners after Welbeck wins a corner with a brilliant individual run. The visitors manage to clear away a couple of crosses, but they look far from comfortable.

Arsenal's supporters are furious when Welbeck is denied a free kick after appearing to be caught by Semih on the edge of the box. It certainly looked like a foul. Surprisingly, we've seen Sneijder playing the deepest of Galatasaray's midfielders early on.

SHOT! Great stuff from Telles and Dzemaili as they exchange passes on the left. The former finds some space on the edge of the box, but his curled effort never threatens Szczesny's goal.

Galatasaray are beginning to come into the game now. The visitors clearly feel that chipped passes over Koscielny and Mertesacker are the way to go tonight as Pandev is only denied a chance by the offside flag. Too much space for the Galatasaray midfielders to work with at the moment.

Great work from Flamini as he stops a counter from the visitors with a perfectly timed challenge on Pandev, who has looked pretty lively when he has got involved. It's been a pretty even start to the game.

Sneijder might not be known for his defensive work, but he does very well to track the run of Ozil and dispossess the German on the edge of the box. Has Prandelli found a new role for the Dutch playmaker?

We've hit a bit of a quiet period in the game. Arsenal are starting to dominate possession, but the pace of their play is slow in the final third of the pitch. Galatasaray are defending superbly well, and are offering very little space to the hosts.

Sanchez produces a piece of magic to leave a couple of Galatasaray defenders behind him on the left wing. The Chilean quickly delivers a ball to the front post, but Melo intervenes to prevent Welbeck from adding the finishing touch.

The Sanchez/Welbeck combination breaks the deadlock! Sanchez shows great feet once again to cut in from the left before sliding through an inch-perfect pass for Welbeck, who slots past Muslera for his first Champions League goal in an Arsenal shirt.

The mood has quickly changed at the Emirates Stadium, and the goal has urged the Gunners forward. Wenger's attacking players are pressing further up the pitch now as they look to make life difficult for Galatasaray. Prandelli looks a very concerned man on the touchline.

Worrying signs for Galatasaray, who have barely had a kick of the ball since falling behind. Arsenal are passing the ball around much quicker now, with Chamberlain leading the charge with his pace and determination on the right. The visitors are struggling with their shape at the back. At times, Melo has been left all alone in the box.

Ozil picks out Welbeck with a clever pass, and the England forward does well to earn himself a yard. However, Sneijder comes to the rescue for his side when he makes a crucial tackle.

We mentioned he needed a big performance. Well, Welbeck is certainly delivering one. It's terrible from the visitors as Welbeck nods the ball past a helpless Melo to go clean through on goal. Not one of the three centre backs manage to catch him, and he finds the back of the net with another calm finish.

CHANCE! It should be a hat-trick for Welbeck, who hits a tame effort straight at Muslera from just inside the box after a Chambers cross was cleared straight to him. Excellent work from Cazorla at the start of the move, too.

CHANCE! Pandev finds a yard of space inside the box, but he fails to test Szczesny while looking for his balance in the box.

YELLOW CARD! Melo is a very lucky boy. He's had a terrible first half, and he really should be off. Replays proves he was off the ground when he challenged Sanchez on the left wing. The referee should have spotted that. Arsenal are fortunate the Chilean is fine to continue.

Unfortunately, the game has had to be stopped for a few moments due to flares being thrown on the pitch by the visiting supporters. Galatasaray skipper Sneijder pleads with the fans to stop, and they seem to be listening. UEFA might have something to say about that incident.

Arsenal are continuing to improve in all areas. Wenger will be delighted with how his side are applying pressure on the ball further up the pitch. Defensively, Galatasaray are in disarray.

Sanchez gets a deserved goal as he drifts away from his marker to collect a pass from Ozil, before cutting onto his right foot and drilling the ball into the bottom corner. It's all too easy for the hosts. This game looks over.

YELLOW CARD! Dzemaili is rightly cautioned after catching Sanchez with a frustrated tackle. Flamini joins him in the book moments later by bringing Sneijder down.

Arsenal will feel that there are plenty more goals to come this evening. Galatasaray's back three don't seem to be sure about who to mark when the Gunners begin to attack. Prandelli has a lot of problems to solve.

It's all Arsenal in the first of two added minutes as they dominate possession. Shouts of "Ole!" from the home fans as the visitors continue to struggle.

What a first half for Arsenal. They needed to produce their best tonight, and they've taken advantage of some terrible Galatasaray defending to open up a commanding lead. Welbeck scored the first two, before Sanchez joined the party by rifling home a third for the Gunners. Three points look to be in the bag.

Is there a way back for Galatasaray? The chances of a comeback look very slim. They started pretty well, but they've been a shambles at the back. Chedjou, Melo and Semih do not look comfortable playing in a back three, and there's been little help from the players in front of them. None of them appear to know who should be marking Welbeck, while Sanchez is a threat each time he cuts in from the left.

As mentioned before the game, Welbeck needed to deliver tonight. He's desperate to prove that he can be the main man for the Gunners in attack, and he found the net twice with excellent finishes while through on goal.

It's worth remembering that Arsenal take on Chelsea at Stamford Bridge on Sunday afternoon. With that in mind, how long will it be until Wenger rests some of his key players? It could also mean that Wilshere is left on the bench this evening to give him more time to be 100% for the game against the Premier League leaders.

30 - Arsenal have won all 30 of their previous Champions League games where they've scored three or more times. Over. — OptaJoe (@OptaJoe) October 1, 2014

SUBSTITUTION: Prandelli has made a change at the break, with Hamit Altintop coming on to replace Yekta. Arsenal will get the game back underway.

Prandelli has changed more than just personnel during the interval. Melo is back in his favoured midfield role, and it looks like Galatasaray have reverted back to four in defence.

Chambers foolishly invites pressure onto himself and eventually concedes a corner. Sneijder attempts to pick out Melo in the box, but Mertesacker rises highest to clear the danger.

It's a good start to the second half for Galatasaray, but they've surely left it too late to trouble the hosts. Mertesacker steps in once again to deny Pandev, who looked to earn himself a yard in the box.

Brilliant from Sanchez as he sprints into space before releasing Chambers, whose cross into the six-yard box is cleared by Semih. He probably should have done better, with Ozil available in the area.

What a night for Welbeck! Arsenal shift the ball to the right for Oxlade-Chamberlain, who executes the perfect pass through the legs Veysel, and Welbeck finishes off the move with a lovely chipped finish over Muslera. Three excellent goals for the forward.

It all seems to be going Arsenal's way. A poor clearance from Koscielny only just evades Yilmaz, fortunately for the home defence, who will be eager to cling onto a clean sheet tonight. Sanchez is everywhere at the moment, and the Gunners fans are loving every minute.

It's party time for the home fans. Arsenal are sharing the ball around with apparent ease, and Galatasaray do not have an answer. Sneijder is attempting to drive his side forward, but he runs out of options on the edge of the box.

Altintop decides it's time for a speculative effort, but he's nowhere near to troubling Szczesny as a 25-yard strike drifts wide of the target.

RED CARD! A perfect evening for Arsenal is ruined as Szczesny storms off his line in an attempt to gather the ball, but he can only bring down Yilmaz in the box. It's a PENALTY for the visitors. Sanchez is the man sacrificed as Wenger sends on David Ospina. The Chilean gets a deserved standing ovation.

Yilmaz is made to wait to take the penalty, but he calmly converts after sending Ospina the wrong way. It will surely be only a consolation for the visitors.

It wouldn't be a surprise to see the pace of the game slow down slightly after Szczesny's dismissal. Galatasaray are seeing a lot more of the ball now, and Arsenal are being forced to drop deeper as a result.

SUBSTITUTIONS: An impressive performance from Oxlade-Chamberlain comes to an end as he makes way for Rosicky. There's two more changes for the visitors, with Bruma and Umut Bulut replacing Pandev and Veysel.

SAVE! Ospina makes a simple save to deny Dzemaili, who unleashed an effort from the edge of the box after Flamini had failed to close him down.

Arsenal deserve credit for how they've responded to the red card. The match may be won, but they're making the pitch look a lot more narrow as Galatasaray see more of the ball. There's some worrying signs on the bench, though, with Sanchez needing ice on his foot.

CHANCE! Cazorla and Ozil play the ball around brilliantly on the edge of the box, before the former chips an inviting ball into the danger zone. Welbeck heads over on the stretch, but he should have left it to Rosicky, who was all alone at the back post.

SHOT! Sneijder sends out a warning to the Gunners as he fires a powerful effort just past the post after being gifted too much space on the edge of the box.

SUBSTITUTION: Wenger decides it is time to send on Wilshere as a tired Ozil makes way for the midfielder.

SHOT! Melo has improved since the break, and he misses the top corner by a yard with a speculative strike from 30 yards out.

In truth, that red card has killed the game off a bit. Galatasaray lost this match in the first half, and they're still being out-fought by the hosts in crucial areas of the pitch.

SAVE! Does anyone have a camera going spare? Ospina makes the most dramatic of saves to deny Yilmaz, who probably should have scored with a header from close range.

Welbeck comes close to doing something very special. He flicks the ball over one defender, before sprinting past two more. Unfortunately, his touch lets him down at the crucial moment and the visitors manage to clear.

SAVE! Ospina does well again to keep out Altintop, whose powerful strike from a tight angle was stopped by the Colombian's legs.

SHOT! Sneijder is agonisingly close to pulling another goal back, but Koscielny gets a vital deflection on his shot to prevent his side from conceding a second.

SAVE! Sneijder seems to be on a mission to get a goal as he targets the bottom corner once again from the edge of the box. However, Ospina responds well to tip the ball past the post.

Brilliant defending from Koscielny as he comes across to dispossess Yilmaz just as the forward was looking to shoot from inside the box. Yilmaz collided with Ospina a moment later, and both require some treatment on the pitch.

Luckily for the two players it looks like they are fine to continue. Not long left at the Emirates Stadium, but there should be a few minutes of stoppage time added on.

The fourth official confirms there will be four minutes of stoppage time played. Galatasaray are on the front foot at the moment, but it looks set to be an emphatic win for the Gunners.

Very little happening in added time, but the Arsenal fans are enjoying themselves as the final whistle approaches. Wilshere almost finds Welbeck with a through ball until an offside flag stops their progress.

CHANCE! Arsenal are inches away from wrapping up the win in style. Welbeck picks out Wilshere, who lobs a brilliant pass over the top to Cazorla. The Spaniard manages to chip the ball over Muslera, but Semih recovers well to clear the ball before it can cross the line.

It's all over at the Emirates, and there is only one man who will be stealing the headlines for the Gunners. Welbeck's hat-trick and a goal from Sanchez has earned Arsenal all three points, and not even a red card for Szczesny can ruin the mood in North London.

That's all from our live coverage tonight, but make sure you keep an eye out for the analysis and reaction. Goodnight everyone.