The Hammers manager had previously promised to focus on the FA Cup after his side had secured Premier League safety, but that has now been ruined following the heavy defeat at The Hawthorns.
Allardyce was subjected to abuse from the travelling fans, while his substitutions were jeered as well; despite the fact his side have enjoyed a highly successful season in the Premier League so far.
Despite the criticism from supporters, the manager has refused to blame his players for the loss, which has come at the end of a mixed week for his side in which they lost Andy Carroll for the rest of the season and secured credible draws against top-four hopefuls Manchester United and Southampton.
"Fans get disappointed because there's 6,500 who have travelled up here and we have built the FA Cup to be one of our big successes this year," said Allardyce.
"I am going to defend the players because we couldn't cope with the injury list and fixture list and it has not given us the level we can play at.”
Support the players
Rather than being disappointed by the result, Allardyce says he will support a group of players that he feels gave everything they could in light of their congested fixture list and mounting injuries.
He did however admit that their performance wasn’t good enough, insisting that they were dead on their feet by the end of the hugely demoralising fixture.
"I can't afford to get disappointed in things like that, it's about me supporting the players. They have given everything they could,” he added.
“It wasn't enough but they have done their best. They have given so much in such a short period of time. They were dead on their feet."