Arsenal boss Wenger delighted with Song performance in Borussia Dortmund win
Wenger was pleased with the Cameroon midfielder's contribution for the first goal.
"For the first goal Song did something exceptional for a defensive midfielder," Wenger said.
"I am pleased for him because we had quite a difficult start in midfield in the first half, but we took over in the second half.
"Overall it was a good game. Dortmund are a good team. They started stronger than us but we were patient and intelligent."