Janowitcz is 24
yo. he is mentally weak and. he's never won anything and he will not win anything. sorry to be so blunt. i.e at his age Nole, Rafa and Fed were winning tournaments left and right.
IMHO, the future #1 will be some new kid. Tomic might have a remote chance btw, but I don't believe in his working habits . No matter how you look at it, Djokovic, Nadal and Murray are still in their prime and nobody can touch them. Good old Fed can spank these kids (Janowitcz, Tomic, Dimitrov) when he is 40yo.
Again, I'm pretty sure that a new #1 will be some new kid and we might see Murray or Rafa overtaking Nole but not so sure about that too.
current 'youngsters' simply have nothing to hurt players like Djokovic, Nadal or Murray. I find it strange that nobody can break through. It's actually boring and depressing
. These young guys can't even upset the top 4. 35yo Haas is playing amazing tennis and I'm not saying this because he def. Nole, he just does.