Conrad Smith on yellow card: I haven't got too much grief about it yet

All Blacks centre Conrad Smith against Argentina. Photo / Brett Phibbs

Both Conrad Smith and Steve Hansen were smiling the day after the All Blacks were forced to play Argentina with 13 men in a torrid first World Cup match for the two nations at Wembley Stadium, but both men will be aware such an occurrence in a quarter-final will not be a laughing matter.

The All Blacks were extremely vulnerable once centre Smith joined skipper Richie McCaw in the sinbin at the end of the first half, and although they got away with it thanks to a dominant second-half performance to win 26-16, it was an experience they don't want to repeat in a knockout fixture.

Referee Wayne Barnes gives New Zealand All Blacks centre Conrad Smith a yellow card. Photo / Brett Phibbs

Smith's decision to infringe at a ruck in front of his posts was less silly than McCaw's trip on opposite Juan Martin Fernandez Lobbe, a reflex action the skipper called "dumb" and Hansen described as a "brain explosion", but the result was the same - three points to Nicolas Sanchez and a nervous 10 minutes on the naughty step.

Fortunately for Smith, there were three shots at goal during his time there - one for Sanchez for his indiscretion, one to Dan Carter at the end of the first half which narrowed the deficit to 12-13, and one more to Sanchez after the break. The other piece of luck was that Argentina couldn't cash in on the absence of the pair with a try.

Watch: All Blacks v Argentina highlights

"I was just counting the score," Smith said when asked about his feelings on the sideline.

"Thankfully there were three penalty shots and they take about a minute and a half each so it wasn't a nice feeling sitting there.

"I just wanted the team to do well and from what I saw at the start of the second half there was a real lift so I was pretty excited to get back on. I thought the momentum... had shifted and we looked a better side even though I was off."

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When asked by a French reporter what the younger players in the squad made of the decision by the apparently "wise" Smith to offend, the 33-year-old laughed, saying: "I haven't got too much grief about it yet but I apologised. I think they appreciated it. I made a mistake and I was just keen to make up for it after that."

Hansen said: "Clearly the referees have got a mandate to come down hard on things. You don't have to be a rocket scientist to know that it's better to have 15 on the park rather than 13 like we did at one stage. Discipline is going to be important. We were fortunate to go come through while those guys were off. Sometimes [playing with fewer player] can lift the team but you'd like to think you don't have to do that."

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- By Patrick McKendry in London