That's what I thought but the rules state a defender has to intentionally ground the ball, he clearly didn't do that.

These are the rules:-

Law 21.1 
The ball can be grounded in in-goal:
by holding it and touching the ground with it; or,
by pressing down on it with a hand or hands, arm or arms, or the front of the player’s body from waist to neck.

That's for attacking players. Defenders have to ground it with their hands. It was a great call under a ton of pressure. 

I thought the ref had a great game.
There were lots of arms going up for head contact when it was literally a glance of a shirt sleeve and he kept his nerve.
The try was a try for me.
The defender was fumbling over it and simply fell across it. There was no intention to ground it with body. I'm not sure it would have been grounded even if he'd done that with his hand.


Very exciting finish. Wasn't sure Rovers were going to do it but while they were in the grind at 6-2 it was always possible.

The clause I have quoted doesn`t differentiate between attacking or defending players.  There isn`t any other specific rule.

So it wasn`t a great call by the ref at all.  Just a demonstration of his lack of knowledge of the rules.

Law 21.1 
The ball can be grounded in in-goal:
by holding it and touching the ground with it; or,
by pressing down on it with a hand or hands, arm or arms, or the front of the player’s body from waist to neck.