Arsene Wenger has challenged Arsenal to kick-start their spluttering campaign with a crucial victory in tomorrow morning's (Singapore time) Group D clash against Turkish giants Galatasaray.

Wenger's side have frustrated their manager with a series of flawed displays during a run of one win from their last six matches in all competitions and the Gunners are desperate to stop the rot when Galatasaray visit the Emirates Stadium.

Instead of kicking on since qualifying for the Champions League group stages with a 1-0 victory over another Turkish side Besiktas in late August, the Gunners have become stuck in a rut.

The disappointing sequence includes a comprehensive dismantling in a 2-0 loss to Borussia Dortmund - a scoreline that flattered the lacklustre Gunners - in their Group D opener.

And the latest misstep came against north London rivals Tottenham last Saturday as Arsenal failed to turn their territorial dominance into goals and had to rely on a late equaliser from Alex Oxlade-Chamberlain to salvage a 1-1 draw.

To make matters worse, Wenger's midfield was decimated by injuries at the weekend, with Wales dynamo Aaron Ramsey, captain Mikel Arteta and England international Jack Wilshere all limping off.

Ramsey and Arteta will miss Galatasaray's visit, while Wenger hopes Wilshere can recover from his ankle problem in time to feature.

Wenger revealed yesterday that Arteta (calf) and Ramsey (hamstring) are expected to miss four weeks each.

"To be generous with time, four weeks. If all goes well, three. Arteta is the same, maybe a bit quicker. It will be after the international break," he said.

Despite the injuries, Wenger knows a win over Galatasaray is essential if Arsenal are to avoid putting themselves in an awkward position in their battle to qualify for the knockout stages of Europe's elite club competition.

"The positive is that we are unbeaten (in the Premier League), but the negative is that we have missed four points from the quality of the games we have played," Wenger said.

"Somewhere we have to keep that unbeaten record and I think at some stage we will win the games instead of drawing.

"It is the second important block (of matches) now. The first massively important game for us was Besiktas after the World Cup to get through and to start well in the Premier League.

"Our start was decent and now is the second block of games that will show how strong and good we are."

Galatasaray haven't won in nine visits to English clubs, but coach Cesare Prandelli insists his team, who drew their Group D opener 1-1 against Anderlecht, have the ability to shock Arsenal.

"In this group, there are strong teams, but we have a chance against Arsenal if we keep fighting," said the former Italy national coach.

Meanwhile, Wenger confirmed yesterday Olivier Giroud will sign a new contract with Arsenal barring the formalities.

When asked about the situation with Giroud, currently out injured with an ankle problem, Wenger said: "It is done.

"We want stability and to keep the core of our team together. Giroud is an important player here.

"It is agreed. When it is completely done, we will announce it."

- Wire Services.

"It’s obviously a great honour and privilege to be in charge for such a long time at such a great club. I just want to be at the expectation level of this club and win tomorrow’s game. Our job is to win the next game." 

- Arsene Wenger on his 18th anniversary at Arsenal tomorrow

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