The German international came off the bench to grab the winning goal late on to ensure Arsenal left Brentford with all three points.
An excellent cross from Bukayo Saka with just minutes left to play was headed home by Havertz at the back post.
“I think the most important is always the team,” he said afterwards, “and to have the three points is very good for me as well, personally you know. I worked quite hard to get these moments again and today, I got it so I’m very, very happy.
“We came here to win and it’s a very good feeling to go home with three points.”
It was Havertz’s’ second goal of the season, and it was a significant one as it sent the Gunners to the top of the table.
“The ball was perfect,” he said of Saka’s cross to the far post. “That’s something we also trained a lot in training and I thought maybe I go there, so hopefully the ball arrives and it arrived perfect so I’m happy to score.”
“It’s always good to be up top but you have to look game by game and still so many games to play, such a long season. You just have to focus on ourselves, win the games and then see at the end what’s going to happen,” Havertz added.
Arsenal face Lens at the Emirates in the Champions League on Wednesday, before another home match against Wolves on Saturday, where they will be hoping to make it three League wins in a row.