The Toon captain is under pressure after last week's dismal defeat at Manchester City.
Carver said: "I think he's been great for me. The goal (Edin) Dzeko scores, he might have done a little bit better with but we never had any pressure on the ball.
"He's the captain of this team and he holds us together and he's been outstanding in my opinion and the staffs' opinion, and the players' opinion in the games that we've been playing.
"Of course (he's a leader) he's huge for us, with his personality. There's not many proper leaders in the Premier League if I'm perfectly honest. Whenever you sit with coaches and managers, that's what they're all asking for. They're all saying we need to find a leader.
"And we do rely on him (Colo). He's been a great servant to this football club and the fans, as far as I'm concerned, do like him. Everybody's going to get criticised, I'm going to get criticised and sometimes you have to take that on the chin and deal with it, especially after the result we've just had."