Rugby World Cup 2019: All Blacks lock Scott Barrett has learnt valuable lesson from Perth red card

Scott Barrett has some cause for concern, as he prepares to take the field for the All Blacks on Saturday night.

The towering lock forward returns to the starting line up against the Springboks in Yokohama - the All Blacks' opening test of Rugby World Cup 2019. 

It marks Barrett's first start since being sent off in Perth against the Wallabies last month for a reckless shoulder charge on Australian skipper Michael Hooper. 

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The referee that night - Frenchman Jerome Garces, who will coincidently officiate the clash with South Africa.

But Barrett believes he has learnt his lesson, telling media that he has worked on his tackling technique.

 "There's obviously a fine line," Barrett said. "I've learnt from that and I'm keen to move on. 

"The laws are there for a reason - to protect players and player welfare - so I've been working hard and am keen to address those wrongdoings."

"It's your training, so when you are under pressure and fatigued at the end of a long half, you're going to go back to your habits. 

"Possibly, I had a bad habit in the past, but I've addressed that. Getting the height in the tackle is a big part of that - that's what I've been working on."

Garces has handed out two red cards to All Blacks in recent years - he also gave Sonny Bill Williams his marching orders for a dangerous tackle against the British & Irish Lions in Wellington in 2017.

But Barrett doesn't believe Saturday night's whistleblower is on the hunt for All Blacks foul play. The 25-year-old predicts consistency from all the match officials in Japan. 

"All the refs will be reffing it the same," he said. "We've had the briefing, so we're well aware of how they're going to be ruling high shots or foul play."

The All Blacks have a nine-day break after their World Cup opener, then head to Oita to play Canada on October 2.

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