The Frenchman netted a stunning goal to open the scoring in the 4-1 victory at the Emirates, with 2,000 fans in the stands.
It was Lacazette's first goal since September, and the 29-year-old says the fans played in their part in spurring him on.
He said: "It was amazing - we were so happy to see the fans today it really helped us during the game, even in bad moments they pushed us to play good obviously we played well it was good football. We had two players come back from injury [Pablo Mari and Calum Chambers] so we're really happy for them so it was a good night."
"(The goal was) really good, really nice when fans are behind us. Was not easy for me this last couple of weeks but to see the fans behind me and the team - I really enjoyed tonight so thanks to them.
"Tonight we wanted to enjoy it and to get our fifth win in a row which we did and now we have time to focus again for the derby on the weekend. We just need to rest and see what happens at the weekend."