He also says John Terry tried to bring out the problems into the open, but the players wouldn't back him.
Alan Shearer (talking to the Daily Telegraph): "Harry would be a great England manager.
"At that level, it's about knitting them into a solid group and making them go out and play in a certain system. Harry would do a great job at that.
"We qualified in spectacular style for the World Cup but it was a disaster. I kept saying on television, 'there's something drastically wrong in the dressing room because we're not seeing the players we see in the Premier League'.
"John Terry tried to get a message out, get something out into the open, to clear the air and move forward. His motives were right: he could see big problems, that something was going to come crashing down.
"Capello should know the players and what they want. If he doesn't it's up to somebody else to have a word.
"If the manager didn't listen, then that's his prerogative as manager and it backfired spectacularly. I cannot remember so many poor performances."
"If you go into management, particularly as an Englishman, then ultimately you'd have to look at one day can I be the England manager? I aspire to be the best. Surely the best is being England manager.
"I loved every single minute at Newcastle despite what it brought at the end (relegation and his exit). It was a great experience, dealing with problems every day, the adrenalin rush again.
"If the right job comes along I'll do it but there are a million people looking for the right one. I wouldn't be too arrogant to say I wouldn't go down to a lower league.
"I still get butterflies when England are playing. I think about the times I was out there. I miss walking out of the tunnel, the 90 minutes and the adrenalin rush that I'll never, ever replace."
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