The Hammers climbed out of the drop zone, following their 2-0 win at Upton Park.
Alessandro Diamanti and Carlton Cole scored the goals for West Ham.
Zola told Sky Sports: “It was a big win today, it was a massive game for the result, for the confidence, for many reasons and its been difficult because we started very well and then they created a chance and after that we went a little bit shaky.
“I asked the crowd but then we came back in the game very well. The first goal was fantastic piece for skill from Alessandro and from that moment we got better and better.
“I tell you it’s a matter of confidence, football is a lot about confidence and when you have it on your side, it’s much easier.”