The young Arsenal forward played a starring role in helping his nation defy the odds to beat Uruguay in their opening Group D encounter on Saturday evening, scoring once and bagging an assist.
"If Costa Rica come out with the personality I know the team has, then I know they – and Joel – can damage England," he is quoted as saying by The Mirror.
"I know England are not better. If they are confident to just go and show what they can do, they will beat England.
"My country is small – just a few million people – and people pretty much ignore us. But if my son was Brazilian, for example, he would be famous around the world."
Campbell is poised to face Italy tomorrow.
Next week's encounter kicks off at 5pm.