The Hammers rarely threatened at Ewood Park and Zola was quick to praise centre-halves James Collins and captain Matthew Upson.
"The two centre-backs were vital because of the kind of play they have," said the Italian.
"I think the whole team in the first half was quite bright but I knew as the game became longer and longer the team physically-wise would drop something because of the game we played on Tuesday (the controversial Carling Cup win over Millwall).
"But once again we defended very well and that is something that is very important.
"Considering all the circumstances I am pleased with the team. It is the third game in six days so I have to admit it was quite difficult."