Henderson is 23, which for a goalkeeper is still very young, he's got a lot of football ahead of him, but you can see that he is hungry to play and I think the competition he could bring to De Gea could be the difference maker, or breaker.
Sometimes when you feel to secure in your position that is the moment when you start making mistakes.
It's the same with outfield players, when you think you are untouchable you make more mistakes because you are over-confident."
He (De Gea) is still one of the best goalkeepers in the world, regardless of the mistakes he has made this season. Every goalkeeper, even the greats of the past have all made mistakes throughout the years.
It's David's job to evaluate his performance and I'm sure he knows that he's not doing well and he can do much, much better."