Carroll looked visibly irritated when Allardyce replaced him with Carlton Cole late in the second half, but the former Blackburn boss felt his side needed fresh impetus after Carroll had put in a busy shift as the lone forward.
"He wants to score a goal and he wants me to leave him on for 90 minutes but at the end of the day he put that much effort in, there are a lot of fresh players on the bench," he said.
"There is Carlton Cole, Matt Taylor and Guy Demel who came on and continued to give us that much more energy to find a winner.
"Fresh players with fresh legs can come on and try and push the opposition and try to score a goal. He will be disappointed, I know, but in the end you make the subs for the benefit of everybody to try and win the game."