Newcastle veteran Campbell: Carroll England class
Carroll has set aside severe off-pitch problems to hit seven goals this season and is in line for an international debut in next week's friendly with France.
And former England defender Campbell said: "Andy has a lot to learn and a lot of hard work still to come, but he's a young lad with a lot of ambition and deserves his crack at the England team.
"He is a raw talent - he has lots of energy, is a handful for any defender, good in the air, holds the ball up well and is willing to fight for the cause, both in attack and defence.
"He puts his head in for the ball where a lot of players wouldn't. He has the potential for sure."
Campbell added: "I have spoken to him, not necessarily giving him advice but, of course, if he asked for some, I'd give it to him."