After their Champions League opener in Germany, the Frenchman hails the influence of his Cameroonian team-mate after he helped the side pick up a valuable point away from home
The Gunners drew 1-1 with the German champions, and Koscielny has heaped praise on the Cameroonian midfielder for a dominant display in Dortmund.
Koscielny told the club’s official website: “I think we defended very well - all the team defends together.
“It's very important to have Alex near the centre-backs because he stops the opportunities coming to the other team. It's good for us.
“It was a hard game, Dortmund played very well.
“We defended well, but to concede a goal two minutes before the end was difficult for us.
“We didn't lose, which was good. We have a game at home, and it is important to win that.”
Koscielny also spoke of the new confidence surrounding the London club, and a belief that they can capitalise on this good run of form in their next game in the Premier League against Blackburn Rovers.
He added: “We are in a good place now and we want to go and win at Blackburn.”
Song had been suspended for the last three league games after stamping on Joey Barton in Arsenal’s opening fixture against Newcastle United.
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