Watched it as well- but not 100% sure of the law. I thought it was only a knock on if the ball hit the ground as it hits Roby's head but Carvell gathers it before it hits the ground. Roby surely didn't play at it and it can't be a forward pass as no warrington palyer touched it

It's a knock on if (roughly) the player propels the ball towards the opposition try line and it strikes either the ground or another player before he is able to regather it.

IMO the only arguments that would make it a valid try are

a) Carvell propelled the ball backwards, or

b) It was a ball steal by Roby which Carvell subsequently recovered and the VR played the advantage.

Having not seen it since the numerous replays on Saturday I'm not convinced by either argument.

That's definately the one he's going for having seen it again last night, in fact, i don't see where all this debates come from

its really not going to make a difference now is it arguing over it saints beat us fair and square in the end by more than a try