Walter Mazzarri was completely satisfied after Watford beat Manchester United 3-1 at Vicarage Road on Sunday.
Goals from Etienne Capoue, Camilo Zuniga and Troy Deeney gave the Hornets their first victory over United since 1986.
Mazzarri was over the moon after seeing his Hornets side play well but ultimately lose at home to both Arsenal and Chelsea last month.
"We played very well, even against Arsenal and Chelsea here at home, but we were more unlucky than today," he said.
"I'm very happy for the fans, they told me it was 30 years since Watford beat United, so this win gives us a lot of satisfaction."
He added: "I am very happy for my players, and most of all I am happy for the three points.
"It will give us the confidence to keep working on everything we've been doing up to now.
"It means that my work that we do every day in training is giving its worth now on the pitch."