Rickman lost his battle with cancer last week and his peers, friends and castmates have been offering up fond farewells for days.
"I've always been a little bit in awe of Alan because he's always been incredibly solicitous of me," he said in a statement.
"I wasn't long out of drama school when I first met him. I was quite green and unsure of myself. He seemed to have an instinct for people who were in need of guidance of some kind. This is something I noticed in him in all the contact I've had with him over 30 years. He looked out for people."