King's chronic knee problems prevent him from taking part in full training sessions, so trust on the pitch sometimes has to fill the void of practice time.
Kaboul said: "Ledley is a good player, a massive player. When you play with him it's always good.
"Sometimes we have to guess how he's going to play. But I've known him for a while now so it's OK. You just have to know how he's going to defend, but you can trust him 100 per cent. It's all about confidence. I feel more confident now in the team. I'm happy now."