How who you rule on this?

[kycat1]

A1 throw a pass in from out of bounds on the side of his front court towards his basket for a breaking A2. The pass from A1 is thrown too hard and first hits the backboard and rim before any one else touches it. The ball starts to roll around the rim and for some reason B1 knocks it off the rim. What do you call?
Remember it is a violations to throw in the ball directly from out of bounds. Also remember this is a pass not a shot (from behind the 3 point line). Please give rule(s) used.