Wayne Barnes and his interpretation of the scrum could ultimately determine the outcome of the World Cup final, even if World Rugby tries to de-power the scrum, according to The Independent's Ruaidhri O'Connor.
New Zealand clash with South Africa in the showpiece of this four-year cycle on Saturday night in Saint-Denis, with the Webb Ellis trophy, as well as the bragging rights of the first country to four World Cups on the line.
While many have criticised the way the defending champions South Africa have played in the last four years, New Zealand have often lit the world on fire with their scintillating attacks.
One of the Springboks' strengths, the scrum, has been widely criticised this week, though, a many feel that something as big as a World Cup should not be determined by a restart like the scrum.
With the world watching, the man in the middle, Wayne Barnes, could well dictate how this final is seen across the globe, and his interpretations of the scrum will be heavily scrutinised.
How will the scrum be called?
Speaking on Wednesday Night Rugby, Ruaidhri O'Connor discussed Barnes' interpretations of the scrum so far in this World Cup.
"I wonder about Barnes," O'Connor said. "I actually wonder what influence that Matt Williams clip going viral over the weekend can have.
"Half of the week has been spent talking, outside of the Bongi Mbonambi thing, about the scrum and the importance of the scrum, and whether you should de-power the scrum.
"That decision at the end of the [semi-final between England and South Africa] game, how many different clips have you seen of it from different angles?
"Then you think about Wayne Barnes who was the referee of the Ireland-New Zealand game. After that game the scrum penalties were a massive factor.
"He punished the dominant team in that game. He rewarded the team who were more technically efficient."
"New Zealand have Joe Schmidt and Greg Feek in their armoury, very intelligent men who know how to get messages to referees," O'Connor added.
"The man who advises referees about scrummaging is Mike Cron, who is the former All Blacks scrum coach. I'm not suggesting there's a channel or anything like that, but what they're looking for is what he is telling them to look for.
"He is the man who built the New Zealand scrum over the years. The pictures that they're looking to paint are the ones that New Zealand are also looking to paint. So, there's a bit of advantage there for the New Zealand forwards."
Barnes likes to be the centre of attention
O'Connor has seen a tendency for Barnes to enjoy the spotlight, which could end up counting against the Springboks on Saturday night.
"Barnes likes to be part of the show, I think it's fair to say," O'Connor said. "If you listen to him on the mic, he likes to be a central figure, he likes to control things.
"If he takes against the South African scrum and decides the South African scrum shouldn't be the winning and losing of a World Cup, or if a message comes from World Rugby trying to make this not be the central thing of a World Cup final, it could go a different way and the impact can be diminished."
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