It wasn't an awkward tackle, it was simple, watch it in slow mo and you can easily indentify what occurs. Josh has the arm and is trying to roll starling on his back to slow the play the ball, but he made it difficult for himself by laying on starling with his arm locked in by Franks arm against starlings back, he was trying to roll him over but restricting himself with his other arm.. thats what makes it look so bad.
I know, I'm not that great at painting a visual picture, but you'll know what I mean when you watch the replay of it,