The Czech midfielder scored the only goal of the game on Sunday as the Gunners beat local rivals Tottenham Hotspur to boost their title chances.
Despite admitting that he was pleased to be the match winner at White Hart Lane, Rosicky believes that the team needs to be more offensive in order to mount a serious challenge at the top of the table.
"The team is more important so even if someone else scored I would be glad as long as we won the game," he told the club's official website. "It means a lot because it is a derby and everyone knows how the fans feel about games like that so it is a great win.
"Defensively we were very good but we have to improve offensively if we want to win the league."
Arsenal continue their campaign on Saturday with a trip to league leaders Chelsea.