Allardyce wants his players to respond to the defeat against Wolves next weekend.
“I would like to apologise to the Blackburn fans who made the journey because what they saw was not very good,” he said.
“You might say the first goal was a foul on the keeper but it is neither here nor there because the referee didn’t give it.
“That sort of defending was not good enough to cope with a Manchester United side that was full or running, flair and talent.
“In the end, they mesmerised us. It is not what we wanted or expected but we have to take it on the chin.
“What is important is how we fight back from it.”
He added: “The truth is Manchester United have better players than we do.
“They are hundreds of millions of pounds ahead of where we are and on the margins of finance, we shouldn’t have any chance of winning.
“To combat their quality we have to be dogged, resilient and organised. But sometimes it shows. Unfortunately, this time it did.
“We wanted to give the fans more. Hopefully we will make it up to them next week when we play Wolves.”
