You live and die by your Tight-head Prop.
Scrum master, Mike Cron explains it best “The way a scrum is formed, the actual axis of the scrum where it rotates is the opposition hooker’s right shoulder. Why I say that, is because the scrum’s left side naturally moves forward ahead of the right side, it’s the natural screw or ’tilt’ due to the way it is set up.
Consequently, the tight-head prop is going ‘into the wind’ if you like. Whereas, the guy on the loose-head side, he’s got the wind behind him, so to speak. So as well as the opposition pushing against him, the tight-head prop also has the natural screw of the scrum pushing against him too.
Not only is Tight-head Prop the most important, it’s also the highest paid!