Diamanti arrived at the club from Livorno just before the transfer deadline and has made an instant impression with goals in the reserves and hitting the woodwork against Wigan when he came on for his debut.
Zola is set to start the 26-year-old in the Barclays Premier League clash against Rafael Benitez's side, with the Hammers looking for their second win of the season.
Carlton Cole carried the goalscoring until Zola entered the transfer market and bought the man who helped Livorno get promoted to Serie A.
Diamanti translates as "diamonds" in Italian and Zola believes he has unearthed a gem. He said: "He has some craziness in his eyes so I'm expecting good things from him. He is one of those players that could make a mistake but could create something unexpected. Variety is important and I expect a bit of that from Diamanti.
"He is very good. He came on last week and hit the post so that is a good first impact. I know it will take time because Serie B is a different level and pace. I'm expecting him to adapt but it will take some time."